Acid–base abnormalities in the intensive care unit

198

A TOT = sum of weak acids and proteins in human plasma; ICU = intensive care unit; IL = interleukin; LR = lactated Ringer’s; pCO 2= Partial pres-sure of carbon dioxide in arterial blood; SBE = standard base excess; SID = strong ion difference; SIDe = effective strong ion difference; SIG =strong ion gap.

Abstract

Acid–base abnormalities are common in the critically ill. The traditional classification of acid–base abnormalities and a modern physico-chemical method of categorizing them will be explored.Specific disorders relating to mortality prediction in the intensive care unit are examined in detail. Lactic acidosis, base excess, and a strong ion gap are highlighted as markers for increased risk of death.

Introduction

Deranged acid–base physiology drives admission to a critical care arena for vast numbers of patients. Management of diverse disorders ranging from diabetic ketoacidosis to hypo-perfusion with lactic acidosis from hemorrhagic or septic shock shares a variety of common therapies for disordered acid–base balance. It is encumbent upon the intensivist to decode the deranged physiology and to categorize the disorder in a meaningful fashion to direct effective repair strategies [1].

Besides the traditional classification of respiratory versus metabolic, acidosis versus alkalosis, and gap versus nongap (normal gap), the intensivist benefits from classifying acid–base disorders into three discrete groups: iatrogenically induced (i.e. hyperchloremic metabolic acidosis), a fixed feature of a pre-existing disease process (i.e. chronic renal failure, hyperlactatemia), or a labile feature of an evolving disease process (i.e. lactic acidosis from hemorrhage, shock of any cause). The therapy for, and the outcome from, each of these three categories may be distinctly different. A review of the genesis of acid–base abnormalities is appropriate but will be limited to metabolic derangements, as respiratory acid–base abnormalities are usually reparable with adjustments in sedative or ventilator prescription.

Acid–base abnormality genesis

Traditional paradigms of acid–base abnormalities hinge on generation of protons from the liberation of metabolic acids such as lactate or carbonic acid from increased CO 2. Most traditional views rely on the Henderson–Hasselbach equation to determine the pH and proton concentration. Other attempts at classification rely upon nomograms with imprecise ‘grey zones’ to account for the imprecision in the Henderson–Hasselbach equation solutions. The key fault with these determinations is reliance upon bicarbonate as a determinant of the pH. In 1983, Peter Stewart clarified the physical chemistry principles that describe the independent determinants of proton concentration and pH, allowing the clinician to precisely and accurately determine the pH and to understand the genesis of each acid–base disturbance encountered [2].

The Stewartian methodology relies upon the relationships between ions that completely dissociate at physiologic pH —so-called ‘strong ions’. There exist strong cations (Na +, K +,Ca 2+and Mg 2+) as well as strong anions (Cl –, lactate, and sulphates [most notable in renal failure]). These strong ions establish a readily apparent strong ion difference (SID) that is net strong ion-positive (normal approximately +40). Since human acid–base physiology derives its homeostasis from charge balance, according to the physical chemistry principles articulated by Stewart the SID must be counterbalanced by an equal and opposing charge termed the effective strong ion difference (SIDe) (normal approximately –40). The SIDe negative charge principally stems from the dissociated moieties of plasma proteins (~78% albumin) and phosphate (~20%). The sum of these weak acids is known as A TOT since they exist in a dissociated form (A –) as well as an associated form (AH). When the SID

Review

Clinical review: Acid–base abnormalities in the intensive care unit

Lewis J Kaplan and Spiros Frangos

Yale University School of Medicine, Department of Surgery, Section of Trauma, Surgical Critical Care and Surgical Emergencies, New Haven,Connecticut, USA

Corresponding author: Lewis J Kaplan, Lewis.Kaplan@https://www.wendangku.net/doc/5d18461260.html,

Published online: 20 October 2004

Critical Care 2005, 9:198-203 (DOI 10.1186/cc2912)

This article is online at https://www.wendangku.net/doc/5d18461260.html,/content/9/2/198? 2004 BioMed Central Ltd

199

to guide therapy with Stewart’s physical–chemical method has championed the latter as an ideal means of determining the mechanism, and of uncovering acid–base abnormalities that were unappreciated using traditional classification and interpretation schemes [4].

Lactic acidosis and hyperlactatemia

The most common acid–base abnormality in trauma patients is lactic acidosis from hypovolemic shock and hypoperfusion. Lactic acidosis is a gap metabolic acidosis that is a labile feature of an evolving disease process. As such, lactic acidosis is a final common feature of a variety of processes that engender hypoperfusion, including diabetic ketoacidosis, septic shock, cardiogenic shock, and a variety of intoxica-tions. These entities will therefore not be discussed separately; the discussion will instead focus on the consequences and implications of lactic acidosis regardless of etiology.

Lactate generated from hypoperfusion generates acidosis as the vast amount of lactate produced contributes a strong anion, decreases the SID, and generates protons. In contrast, lactate from lactated Ringer’s (LR) solution is in small quantities (28mmol/l) and is readily consumed, leaving behind Na+as a strong cation; alkalinization results from the more positive SID leading to proton consumption.

Resolution of lactic acidosis correlates well with survival in a time-dependent fashion [5]. Moreover, resolving occult hypoperfusion (normal vital signs, but a persistent lactic acidosis) directly relates to infection risk as well as to mortality [6,7]. Reduced infectious events (principally respiratory complications) were realized using a protocol to clear lactate, whether overt or occult, as an arbiter of underlying hypoperfusion and systemic infection risk.

In order to avoid inappropriate therapy, it is important to differentiate lactic acidemia from hyperlactatemia (normal pH, elevated lactate level, constant lactate/pyruvate ratio). The former indicates a condition that merits therapy (volume expansion, inotropic support, septic source control), while hyperlactatemia frequently stems from exogenous medications, or as an endogenous accompaniment to persistently elevated endogenous catecholamines after shock or trauma [8]. Lactic acidosis has long been utilized as an outcome predictor with regard to survival after trauma, both blunt and penetrating, as well as intra-abdominal catastrophe [5–7,9, 10]. However, lactate also performs quite well in the intensive care unit (ICU) as a mortality gauge [11]. The presence of this potent predictor of outcome is readily identifiable in the ICU setting with physical examination using extremity temperature as an arbiter (exclusive of patients with peripheral occlusive vascular disease) [12].

Lactic acidosis, but not hyperlactatemia [13], closely correlates with mortality risk and serves as a window into cell-level oxygen-dependent processes. Moreover, clearance of lactic acidemia portends an excellent likelihood of survival. In one convenience sampling of surgical ICU patients (general surgery and trauma) comparing lactate and base excess, lactate appears superior in predicting mortality and morbidity [14]. Relatedly, a separate study (prospective, consecutive, mixed medical–surgical patients) found that the combination of the two variables appeared superior to either lactate or base excess alone in predicting survival [15].

Standard base excess (base deficit)

A companion acid–base variable, base excess (commonly presented as base deficit) has also been touted as a prognostic variable in assessing outcome in the critically ill. Base excess indicates metabolic acidosis or alkalosis, but does not help place the acidosis into one or another category with regard to genesis. It is, however, commonly and readily assessed and is therefore the focus of a host of studies. A plethora of studies present a mixed picture in the analysis of base excess since the data derive from two distinct time frames: Emergency Department arrival versus some time after resuscitation. It is in the interpretation of base excess that the Stewart principles are vital to guide interpretation. Indeed, it has been demonstrated that the base excess may be manipulated by fluid resuscitation. Generating a hyper-chloremic metabolic acidosis will create a spuriously more negative base deficit (or increased base excess) as the Cl–decreases the pH unaccompanied by hypoperfusion and lactic acidemia [16]. Prognostication dependent on post-resuscitation standard base excess (SBE) values must therefore be interpreted with caution.

Nonetheless, presentation or pre-resuscitation base excess values reliably indicate the degree of acid production following injury [17]. Interestingly, in this large cohort analysis of presentation SBE, the 50% lethal dose for the acid load indicated by base deficit shifted to a substantially lower level for a given age when combined with a traumatic brain injury; it is unknown whether this is true for other injuries in isolation or combination. The interpretation of SBE must therefore incorporate the injury complex into decision-making, perhaps limiting its utility. A recent study of salvageable trauma patients who underwent arterial blood gas analysis identified that SBE utility was greatest in predicting the outcome of patients sustaining gunshot wounds and blunt injury versus those with stab wounds or lacerations [18]. Mortality was lower for stab/laceration patients at any given base deficit, rendering interpretation in this subgroup problematic. Similar to lactate, the rate of clearance of base deficit to normal, rather than the absolute value, correlates better with survival than do changes in pH [19].

It is important to note that, using an ex vivo model, base excess values are CO2invariate (unlike pH), potentially aiding in their initial utility and interpretation [20]. However, the clinical milieu includes multiple elements that may impact

200

base excess, rendering the CO2–base excess relationship difficult to appreciate. Nonetheless, base excess correlates with transfusion requirements and with length of stay [21].

In patients with major hepatic trauma, base deficit (50% lethal dose, –11.8mmol/l) and 24-hour transfusion requirement (50% lethal dose, 5.4 l packed red blood cells) surfaced as the strongest predictors of the risk of death, outperforming arterial lactate [22]. Importantly, these observations and the model were then tested on a different cohort with only pelvic fractures, with excellent performance. Smaller studies in pediatric trauma patients found that a base deficit less negative than –5 predicted uniform survival since all study group deaths occurred in patients with more negative base deficit values [23]. It thus appears that pre-resuscitation base excess or deficit correlates with survival and serves as another indicator of an underlying disease (hypoperfusion), but interpretation must be tempered by age and the mechanism of injury. Hyperchloremic acidosis

While we touched upon hyperchloremic acidosis earlier, this common iatrogenically induced entity deserves further exploration. As already noted, the genesis of hyperchloremic metabolic acidosis stems from excess chloride administration relative to sodium, commonly as 0.9% normal saline solution, 0.45%normal saline solution, and even LR solution in large quantities [24–26]. This entity is thus an iatrogenic metabolic acidosis of the nongap variety. Hyperchloremia has been identified in up to 80% of patients admitted to a mixed medical–surgical ICU [26]. While not a predictor of outcome, hyperchloremic metabolic acidosis may contribute to morbidity and resource utilization. ICU admission for an ‘unexpected acidosis’, increased and perhaps mechanically supported minute ventilation to compensate for acidosis, and more complex intravenous fluid prescriptions (especially when utilizing hyperalimentation for nutritional support) are but a few ICU care elements impacted by hyperchloremic metabolic acidosis. While these events are probably insignificant for the young and otherwise physiologically sound patients, they may be significantly physiologically challenging for the elderly or for those with physiologic decompensation following significant trauma and hemor-rhagic or septic shock.

The relationship between hyperchloremia and renal dysfunction is well known [27,28]. Moreover, ICU survival has been linked to Acute Pathophysiology and Chronic Health Evaluation II/III scores and multiple organ dysfunction syndrome, of which acute renal failure is a major element [29]. Controversy has long surrounded whether patients die from their renal failure or whether they die from the disease process. Recent data strongly suggest that acute renal failure is an independent risk factor for death despite renal replacement therapy [30]. In this study of acute renal failure, patients requiring renal replacement therapy suffered an accelerated mortality (62.8%) compared with those without renal failure (15.6%). The mortality differences remained unexplained by differences in the severity of illness, thus helping establish acute renal failure as an independent risk factor for mortality. Moreover, complicated acidosis/alkalosis

was independently associated with death.

The deleterious impact of acute renal failure is thus potentially minimized by avoiding iatrogenic hyperchloremia and its attendant compromise of renal function. F urther studies are needed to ascertain the impact of this entity upon current arbiters of morbidity including the ICU length of stay, ventilator days, acute lung injury/acute respiratory distress syndrome, and ventilator-associated pneumonia. Moreover, virtually no research addresses hyperchloremia avoidance strategies and their impact on morbidity such as acute renal failure in at-risk populations, nor addresses mortality.

Both animal and human data identify a linearly decreased pH

and an increased SID with progressive chloride loading

[31–33]. Interestingly, metabolic acidosis induced by chloride from normal saline solution loading is associated

with impaired coagulation and the need for bicarbonate buffering of the induced acidosis, while resuscitation with comparable amounts of LR solution required no such therapy [31,33]. Hyperchloremic acidosis, while not a predictor of outcome, may therefore serve as a sentinel for hemorrhage risk, for component transfusion therapy, and for accelerated resource utilization. Importantly, one ex vivo study noted the induction of a SIG with crystalloid-induced hyperchloremic acidosis; no SIG was induced by adding comparable amounts of large molecular weight hydroxyethyl starch [31].

In a related provocative study, sepsis survival was enhanced

by resuscitation with a large molecular weight hydroxyethyl starch molecule suspended in a balanced salt solution compared with LR solution or saline, and was unassociated

with hyperchloremic metabolic acidosis [34].

Immune effects of acidosis

The effects of metabolic acidosis span more than one system. Immune activation has been intimately linked to the presence

of acidosis, and SIG generation may be but one feature. Crystalloid resuscitation serves as a potent trigger for human

white blood cell count activation, manifested as an oxidative

burst and the expression of cell surface adhesion molecules [35]. Activation of T-cell protein kinases has been demon-strated with hypertonic saline, an effect whose downstream

cell-specific responses carry an uncertain significance [36].

More certainly, intravascular acid infusion reliably creates

acute lung injury and increases exhaled nitric oxide concentration in a rat model [37]. This effect has been demonstrated to stem from acidosis-stimulated expression of inducible nitric oxide synthase, and was associated with elaboration of the proinflammatory cytokine IL-6, also in a rat preparation [38]. Importantly, this work suggests that correction of acidosis may ameliorate inducible nitric oxide synthase expression and reduce lung injury.

201

Relatedly, acidosis included by lactate, pyruvate or HCl has been recently demonstrated to increase whole blood viscosity at both high and low shear rates of flow. During acidosis induction, hematocrit increases reflecting red blood cell swelling were also observed. Most importantly, these rheologic changes were reversible with the correction of acidosis. These data lend support to the notion that correcting acidosis represents more than ‘treating numbers’and instead addresses important cellular and subcellular events. It is possible that the increased viscosity and hematocrit is responsible, in part, for regional hypoperfusion despite normal or supranormal systemic flow. Clearly further study is warranted, but one must consider that the time-honored endpoint of mortality is not well suited to assess the interventions targeting acid–base balance. Measures of morbidity or resource utilization may be more appropriate instead.

Strong ion gap

There are several studies that either support [39,40] or decry the utility of the Stewart methodology in evaluating ICU patients [26,41,42]. The SIG, as determined by Stewart’s physico-chemical method, is strongly associated with metabolic acidosis, but is an independent entity that is probably a labile feature of an evolving disease process. One element that has surfaced from these studies is that the Stewart methodology is a precise and readily utilizable means of identifying the nature of the metabolic aberration; a calculator to determine the individual components is downloadable from the Internet [43]. How may one resolve the seeming disparity of SIG utility identified in some studies that is conspicuously lacking in others? The answer may be found in the timing. Much like base excess, the value of the SIG may be related to the time of assay. Since the natural history of the SIG and its clearance value remains unknown (similar to the early lactate observations), we must look to pre-resuscitation SIG analysis as a more controlled evaluation scheme.

In patients with major vascular injury requiring operative repair, but prior to resuscitation, an increased SIG (>5) is predictive of mortality [44]. Performance characteristics based on receiver–operator characteristic curve analysis indicated a SIG area of 0.991 for mortality (95% confidence interval, 0.972–0.998) and that for anion gap of 0.994 (95% confidence interval, 0.976–0.999), outperforming lactate (receiver–operator characteristic curve area, 0.981; 95% confidence interval, 0.957–0.993). Multivariate logistic regression analysis indicated that an increased SIG (odds ratio, 3.6; 95% confidence interval, 1.99–6.78), more strongly than injury severity score(odds ratio, 1.17; 95% confidence interval, 1.06–1.31), was predictive of mortality. In a related study in unselected trauma patients, the SIG discriminated quite well between survivors and those who died within 72hours of Emergency Department arrival, again outperforming lactate and base deficit [45]]. While the absolute SIG levels were not identical, the import behind the elevated level remains unaltered. It may be that the degree of SIG elevation is disease specific. An increased SIG occurs in patients with hepatic dysfunction [46] and renal dysfunction [26], as well as during endotoxin-induced sepsis [47]. In a large retrospective database analysis of patients requiring ICU care, SIG >2 was independently linked with mortality in patients evidencing metabolic acidosis [48].

Based on these studies, longitudinal assessments of changes in the SIG as a predictor of outcome are underway. Nonethe-less, it seems prudent to incorporate the pre-resuscitation SIG into the mélange of information that guides outcome prognostication. These data may be incorporated into daily practice using a handheld calculator, or a computer-based macro utilizing the relevant data points from the clinical laboratory; automated abstraction is ideal but awaits the development of appropriate interfaces with existing laboratory devices. It is essential to note that no evaluation method besides the physico-chemical one of Stewart allows the clinician to ascertain the presence and magnitude of the SIG. Conclusion

Traditional classification schemes of acid–base derange-ments are too broad to aid in prognostication. Individual acid–base element evaluation allows one to draw valid conclusions regarding the likelihood of survival. The Stewart physico-chemical approach to acid–base analysis readily lends itself to these determinations by precisely evaluating the independent determinants of pH as well as the important SIG. At present, lactate, pre-resuscitation base deficit and the SIG appear most predictive of outcome in the critically ill, and they should be incorporated into a prognostication method. F uture studies of acid–base prediction of outcome should strongly consider including each of these variables in their methodology. F urther evaluation of these and potentially other markers of morbidity and resource utilization is appropriate. Competing interests

The author(s) declare that they have no competing interests. References

1.Gunnerson K, Kellum JA: Acid–base and electrolyte analysis in

critically ill patients: are we ready for the new millennium?

Curr Opin Crit Care2003, 9:468-473.

2.Stewart PA: Modern quantitative acid–base chemistry.Can J

Physiol Pharm1983, 61:1444-1461.

https://www.wendangku.net/doc/5d18461260.html,ler L, Waters JH: Mechanism of hyperchloremic nonanion

gap acidosis.Anesthesiology1997; 87:1009-1010.

4.F encl V, Jabor A, Kazda A, F igge J: Diagnosis of metabolic

acid–base disturbances in critically ill patients.Am J Respir Crit Care Med2000, 162:2246-2251.

5.Abramson D, Scalea TM, Hitchcock R, Trooskin SZ, Henry SM,

Greenspan J: Lactate clearance and survival following injury.J Trauma1993, 35:584-589.

6.Claridge JA, Crabtree TD, Pelletier SJ, Butler K, Sawyer RG,

Young JS: Persistent occult hypoperfusion is associated with

a significant increase in infection rate and mortality in major

trauma patients.J Trauma2000, 48:8-14.

202

7.Blow O, Magliore L, Claridge JA, Butler K, Young JS: The golden

hour and the silver day: detection and correction of occult hypoperfusion within 24 hours improves outcomes from major trauma.J Trauma1999, 47:964-969.

8.James JH, Luchette FA, McCarter FD, Fischer JE: Lactate is an

unreliable indicator of tissue hypoxia in injury or sepsis.

Lancet1999, 354:505-508.

9.Jeng JC, Jablonski K, Bridgeman A, Jordan MH: Serum lactate,

not base deficit, rapidly predicts survival after major burns.

B u rns 2002, 28:161-166.

10.Mikulaschek A, Henry SM, Donovan R, Scalea TM: Serum lactate

in not predicted by anion gap or base excess after trauma resuscitation.J Trauma 1996, 40:218-224.

11.Mizock BM, Falk JL: Lactic acidosis in critical illness.Crit Care

Med1992, 20:80-93.

12.Kaplan L, McPartland K, Santora TA, Trooskin SZ: Start with the

physical examination to identify hypoperfusion in ICU patients. J Trauma2001, 50:620-628.

13.Mizock BM: Significance of hyperlactatemia without acidosis

during hypermetabloic stress.Crit Care Med1997, 25:1780-1781.

14.Husain FA, Martin MJ, Mullenix PS, Steele SR, Elliott DC: Serum

lactate and base deficit as predictor of mortality and morbid-ity.Am J Surg2003, 185:485-491.

15.Smith I, Kumar P, Molloy S, Rhodes A, Newman PJ, Grounds RM,

Bennett ED: Base excess and lactate as prognostic indicators for patients admitted to intensive care.Int Care Med2001, 27:74-83.

16.Brill SA, Stewart TR, Brundage SI, Schreiber MA: Base deficit

does not predict mortality when secondary to hyperchloremic acidosis.Shock2002, 17:459-462.

17.Rutherford E, Morris JA, Reed GW, Hall KS: Base deficit strati-

fies mortality and determines therapy.J Trauma1992, 33:417-423.

18.Tremblay L, Feliciano DV, Rozycki G: Assessment of initial base

deficit as a predictor of outcome: mechanism of injury does make a difference.Am Surg2002, 68:689-693.

19.Davis J, Kaups KL, Parks SN: Base deficit is superior to pH in

evaluating clearance of acidosis after traumatic shock.

J Trauma1998, 44:114-118.

20.Morgan TJ, Clark C, Endre Z: Accuracy of base excess — an in

vitro evaluation of the Van Slyke equation.Crit Care Med 2000, 28:2932-2936.

21.Davis JW, Parks SN, Kaups KL, Gladen HE, O'Donnell-Nicol S:

Admission base deficit predicts transfusion requirements and risk of complications.J Trauma1996, 41:769-774.

22.Siegel JH, Rivkind AI, Dalal S, Godzari S: Early physiologic pre-

dictors of injury severity and death in blunt multiple trauma.

Arch Surg1990, 125:498-508.

23.Randolph LC, Takacs M, Davis KA: Resuscitation in the pedi-

atric trauma population: admission base deficit remains an important prognostic indicator.J Trauma2002, 53:838-842. 24.Scheingraber S, Rehm M, Sehmisch C, Finsterer U: Rapid saline

infusion produces hyperchloremic acidosis in patients under-going gynecologic surgery.Anesthesiology1999, 90:1265-1270.

25.Hayhoe M, Bellomo R, Liu G, McNicol L, Buxton B: The aetiology

and pathogenesis of cardiopulmonary bypass-associated metabolic acidosis using polygeline pump prime.Int Care Med1999, 25:680-685.

26.Moviat M, van Haren F, van der Hoeven H: Conventional or

physicochemical approach in intensive care unit patients with metabolic acidosis.Crit Care2003, 7:R41-R45.

27.Wilcox CS: Regulation of renal blood flow by plasma chloride.

J Clin Invest1983, 71:726-735.

28.Williams EL, Hildebrand KL, McCormick SA, Bedel MJ: The

effect of intravenous lactated ringer’s solution versus 0.9% sodium chloride solution on serum osmolality in human vol-unteers.Anesth Analg1999, 88:999-1003.

29.Barie P, Hydo LJ, Fischer E: Utility of severity scoring for pre-

diction of prolonged critical care.J Trauma1996, 40:513-519.

30.Metnitz PG, Krenn CG, Steltzer H, Lang T, Ploder J, Lenz K, Le

Gall JR, Druml W: Effect of renal failure requiring renal replacement therapy on outcome in critically ill patients.Crit Care Med2002, 30:2051-2058.

31.Patterson T, Bailey H, Kaplan LJ: Hyperchloremia induces aci-

dosis, increases the strong ion gap, and impairs coagulation [abstract].Crit Care Med2000, Suppl28:A118.32.Healey, MA, Davis RE, Liu F C, Loomis WH, Hoyt DB: Lactated

ringers in superior to normal saline in a model of massive

hemorrhage and resuscitation.J Trauma 1998, 45:894-899.

33.Waters JH, Gottlieb A, Schoenwald P, Popovich MJ, Sprung J,

Nelson DR: Normal saline versus lactated ringer’s solution for

intraoperative fluid management in patients undergoing

abdominal aortic aneurysm repair: an outcome study.Anesth

Analg2001, 93:817-822.

34.Kellum JA: Fluid resuscitation and hyperchloremic acidosis in

experimental sepsis: improved short-term survival and

acid–base balance with Hextend compared with saline.Crit

Care Med2002, 30:300-305.

35.Rhee P, Wang D, Ruff P, Austin B, DeBraux S, Wolcott K, Burris

D, Ling G, Sun L: Human neutrophil activation and increased

adhesion by various resuscitation fluids. Crit Care Med2000,

28:74-78.

36.Junger WG, Hoyt DB, Hamreus M, Liu FC, Herdon-Remelius C,

Junger W, Altman A: Hypertonic saline activates protein

kinases and mitogen-activated protein kinase p38 in T-cells.J

Trauma1997, 42:437-443.

37.Pedoto A, Caruso JE, Nandi J, Oler A, Hoffmann SP, Tassiopoulos

AK, McGraw DJ, Camporesi EM, Hakim TS: Acidosis stimulates

nitric oxide production and lung damage in rats.Am J Respir

Crit Care Med1999, 159:397-402.

38.Haque IU, Huang CJ, Scumpia PO, Nasiroglu O, Skimming JW:

Intravascular infusion of acid promotes intrapulmonary

inducible nitric oxide synthase activity and impairs blood oxy-

genation in rats.Crit Care Med2003, 31:1454-1460.

39.Kellum JA: Metabolic acidosis in the critically ill: lessons

learned from physical chemistry.Kidney Int1998, 53 (Suppl

66):S81-S86.

40.Balasubramanyan N, Havens PL, Hoffman GM: Unmeasured

anions identified by the Fencl–Stewart method predict mortal-

ity better than base excess, anion gap, and lactate in patients

admitted in the pediatric intensive care unit.Crit Care Med

1999, 27:1577-1581.

41.Hatherill M, Waggie Z, Purves L, Reynolds L, Argent A: Mortality

and the nature of metabolic acidosis in children with shock.

Int Care Med2003, 29:286-291.

42.Cusack RJ, Rhodes A, Lochhead P, Jordan B, Perry S, Ball JA,

Grounds RM, Bennett ED: The strong ion gap does not have

prognostic value in critically ill patients in a mixed

medical/surgical adult ICU.Int Care Med2002, 28:864-869.

43.Kellum JA (Ed): The Acid Base pHorum [https://www.wendangku.net/doc/5d18461260.html,m.upmc.

edu/education/resources/phorum.html], accessed 10 December

2003.

44.Kaplan LJ, Kellum JA: Initial pH, base deficit, lactate, anion gap,

strong ion difference and strong ion gap predicts outcome

from major vascular injury.Crit Care Med2004, 32:1120-

1124.

45.Kaplan LJ, Bailey H, Klein A, et al.:Strong ion gap: a predictor of

early mortality following blunt or penetrating trauma

[abstract].Crit Care Med1999, Suppl27:A42.

46.Kellum JA, Kramer DJ, Pinsky MR: Strong ion gap: a methodol-

ogy for exploring unexplained anions.J Crit Care 1995, 10:51-

55.

47.Kellum JA, Bellomo R, Kramer DJ, Pinsky MR: Hepatic anion flux

during acute endotoxemia.J Appl Physiol1995, 78:2212-

2217.

48.Gunnerson KJ, Saul M, Kellum JA: Lactic versus nonlactic meta-

bolic acidosis: outcomes in critically ill patients[abstract]. Crit

Care2003; 7(Suppl 2):S8.

203

药学毕业论文齐墩果酸和熊果酸保护神经的药理作用综述

齐墩果酸和熊果酸保护神经的药理作用综述 齐墩果酸和熊果酸是通过抗氧化、抗炎而产生神经保护 作用，以下是搜集整理的一篇相关论文范文，欢迎阅读参考。 齐墩果酸(oleanolicacid)和熊果酸(ursolicacid)同属 五环三萜酸类化合物，它们又是同分异构体，因此药理作用几乎 相同。现已证实齐墩果酸和熊果酸都具有抗炎、降糖、调脂、抗 肥胖、抗动脉粥样硬化药理作用[1-4],有望成为抗代谢综合征新药。代谢综合征可诱发神经系统方面的并发症，如脑中风、疼痛、糖尿病脑病、痴呆等。我国正在步入老龄社会，尤其是很多大城 市已经进入老龄社会，老年性神经精神疾病如老年痴呆、帕金森 病等发病率快速增长，而目前又缺乏安全有效、毒副作用低的防 治老年性神经精神疾病药物。齐墩果酸和熊果酸除了通过抗代谢 综合征阻滞神经系统并发症外，已有大量实验研究发现齐墩果酸 和熊果酸具有神经保护作用。本文综述齐墩果酸和熊果酸保护神 经细胞、镇痛、抗精神失常、改善学习记忆等神经精神药理方面 的研究进展，为齐墩果酸和熊果酸防治老年痴呆、帕金森病和抑 郁症的研发提供依据。 1、对离体神经细胞的保护 β淀粉样肽、过氧化氢、谷氨酸、6-羟基多巴胺等都具 有神经毒性作用，能直接损伤神经细胞引起的神经元凋亡和神经 功能障碍。齐墩果酸和熊果酸对这些神经毒素引起的离体神经细 胞损伤都有保护作用。 1.1对抗β淀粉样肽的神经毒性

PC12细胞源自大鼠髓质嗜铬细胞瘤，为神经源性细胞，具有多巴胺能神经特性，被广泛用作神经细胞体外模型，常被用来筛选神经保护药物。齐墩果酸(20、40、80mg/L)预处理PC12细胞，可浓度相关地对抗β淀粉样肽诱导乳酸脱氢酶渗漏，提高PC12细胞存活率，降低细胞凋亡率。这种神经保护作用可能与齐墩果酸促进抗凋亡基因bcl-2表达，抑制促凋亡基因bax表达有关[5].Hong等[6]报道熊果酸0.5~125μmol/L浓度相关的抑制β淀粉样肽诱导PC12细胞产生活性氧，从而减少DNA断裂和细胞凋亡。也可通过抑制上游激酶ERK1/2、p38和JNK磷酸化，阻滞核因子-κB(NF-κB)的p65亚单位核易位，抑制β淀粉样肽诱导PC12细胞表达诱生型一氧化氮合酶和环氧化酶-2,阻止神经炎症反应发生[7].Wilkinson等[8]报道熊果酸阻滞β淀粉样肽与小神经胶质细胞结合并抑制活性氧生成。用表达人CD36的中国仓鼠卵巢细胞实验，发现熊果酸浓度相关地阻滞β淀粉样肽与其受体CD36结合，浓度增至20μmol/L时作用达到峰值，最大抑制率为64%,认为熊果酸通过阻滞β淀粉样肽与CD36结合，抑制前炎性细胞因子和神经毒活性氧产生，从而阻断神经变性发生。 1.2对抗过氧化氢的神经毒性 Yu等[9]报道熊果酸0.05~2mg/L通过诱生抗氧化酶过氧化氢酶、谷胱甘肽过氧化物酶和抑制脂质过氧化反应，对抗过氧化氢损伤HEI-OC1听觉细胞。Rong等[10]报道齐墩果酸1、 10μmol/L可对抗过氧化氢损伤PC12细胞，表现为显着降低乳酸脱氢酶活性和丙二醛水平，逆转低下的线粒体膜电位、琥珀酸脱氢酶和超氧化物歧化酶活性、还原型谷胱甘肽水平，从而提高 PC12细胞存活率。Cho等[11]报道齐墩果酸通过对抗过氧化氢升高细胞内钙离子浓度和活性氧生成，抑制过氧化氢诱导大鼠皮质神经元凋亡。

熊果酸含量测定方法研究进展

熊果酸含量测定方法研究进展 （作者:___________单位: ___________邮编: ___________） 【关键词】熊果酸；含量测定方法 熊果酸（ursolie acid，UA）又名乌索酸、乌苏酸，属于三萜类化合物，广泛存在于熊果、白花蛇舌草、女贞子、乌梅等天然植物和草药中，具有抗炎、护肝、降血脂等多种生物学活性［1～4］。目前许多中药材及其制剂常选用熊果酸的含量作为其质量控制指标。本文对熊果酸含量测定方法的研究进展综述如下。 1 分光光度法 李国章等［5］建立了湘产3种苦丁茶中熊果酸含量测定的分光光度法，具体操作是取苦丁茶经索氏提取器提取后，加入5%香草醛－冰醋酸、高氯酸显色，在波长548 nm处测定吸光度，结果熊果酸在4～20 μg·ml-1浓度范围内线性关系良好，加样回收率为98.96%。罗启剑等［6］采用同样方法测定了连钱草中熊果酸含量，结果熊果酸在0～18 μg·ml-1浓度范围内线性关系良好，加样回收率为100.64%。 2 薄层扫描法

白洁等［7］采用双波长薄层扫描法测定了夏枯草中熊果酸的含量，具体操作为取夏枯草药材粗粉经95％乙醇超声提取两次，滤液用70℃水浴蒸干，残渣用石油醚浸泡两次，挥干溶剂，用95％乙醇溶解后测定。采用硅胶G板，以环己烷－氯仿－醋酸乙酯（20∶5∶8）为展开剂，用10％硫酸乙醇溶液显色，选用λS=540 nm，λR=700 nm进行双波长反射式锯齿扫描，结果熊果酸在0.314～1.570 μg范围内线性关系良好，加样回收率为99.3％。张军等［8］建立了狼疮静颗粒中熊果酸的薄层扫描法测定方法，具体操作为取狼疮静颗粒用乙醚萃取3次，合并乙醚萃取液水浴蒸干乙醚，残留物加无水乙醇－氯仿（3∶2）混合液溶解后测定，以环己烷－氯仿－醋酸乙酯－甲酸（20∶5∶8）为展开剂，用10％的硫酸乙醇液显色，以λS=520 nm，λR=700 nm进行双波长薄层扫描，结果熊果酸在0.498～3.084 μg范围内线性关系良好，加样回收率为97.91％。 3 高效液相色谱法 3.1 HPLC－UV法戚志华等［9］采用HPLC法测定了陕西女贞子中熊果酸的含量，其方法为取女贞子粉末经超声提取后采用HPLC法，选用Lichrospher C18（ 4.6 mm×250 mm，5 μm）色谱柱，流动相为乙腈－甲醇－水－磷酸－三乙胺（50∶30∶20∶0.02∶0．04），流速1 ml·min-1，测定波长为205 nm，结果熊果酸在20.48～102.4 μg范围内线性关系良好，加样回收率为100.6％。梁洁等［10］采用HPLC法测定了广西产美味猕猴桃根中熊果酸的含量，具体操作为取

乌梅药材中齐墩果酸和熊果酸的高效液相色谱含量测定(一)讲解

乌梅药材中齐墩果酸和熊果酸的高效液相色谱含量 测定(一) 作者：范成杰，刘友平，陈鸿平，石宇华 【摘要】目的应用高效液相色谱（HPLC）法测定乌梅药材中齐墩果酸和熊果酸的含量，并以齐墩果酸和熊果酸为指标成分建立乌梅肉的质量标准。方法采用Hypersil ODS C18(150 mm×4.6 mm, 5 μm)；甲醇－0.2%乙酸铵水溶液（83∶17）为流动相；检测波长210 nm，流速0.8 ml/min，柱温25℃。结果 齐墩果酸的线性范围为0.168～1.512 μg，r＝0.999 6，回收率为98.00%（RSD=0.53%）；熊果酸的线性范围为0.452～4.068 μg，r=0.999 9，回收率为97.13%（RSD=1.17%）。结论该方法简便、可靠、准确，可用于乌梅药材中 齐墩果酸和熊果酸的含量比较和乌梅肉的质量控制。 【关键词】高效液相色谱法乌梅肉齐墩果酸熊果酸 Abstract：ObjectiveTo determine the ursolic acid and oleanolic acid in the pulp of Fructus Mume by HPLC. MethodsThe ursolic acid and oleanolic acid were separated on C18 column.Methanol-0.2% Ammonium acetate solution (83∶17) was used as mobile phase and the detection wavelength was 254nm.ResultsThe linearity of ursolic acid and oleanolic acid was in the range of 0.168～1.512μg, 0.452～4.068μg, respectively; the average recoveries of ursolic acid and oleanolic acid were 98.00%(RSD=0.53%,n=5) and 97.13%(RSD=1.17%,n=5). ConclusionThe method is simple, quick and reproducible，and it can be used for the quality control of the pulp of Fructus Mume. Key words：HPLC; Pulp of Fructus Mume; Ursolic acid; Oleanolic acid 乌梅，别名酸梅、黑梅，由蔷薇科植物梅Prunus mume (Sieb.) Sieb. et Zucc.（Armeniaca mume Sieb.）的干燥近成熟果实加工而成。关于乌梅的入药方式，历代本草记载有去核和连核使用两种，现代研究证明乌梅中有效成分有机酸及水浸出物大多集中在果肉中，核含量甚少〔1〕，且核仁含大量脂肪油成分，具滑泄作用，与乌梅的固涩作用相驳；同时也有报道认为乌梅核特征明显，有利于乌梅的鉴定，而且乌梅核还含有约5％的有机酸，且去核繁琐费时 费工〔2〕，所以乌梅是否应分部位药用仍存在争议。《中国药典》Ⅰ部（2005年版）中，净乌梅和乌梅肉都有收载〔3〕。因此明确乌梅的入药方式，是建立乌梅规范的质量标准的前提。本课题组前期对乌梅各部位的化学成分进行了初步比较研究，结果表明乌梅各部位的药理作用不同，代表乌梅涩肠止泻作用的主要药用部位为乌梅果肉。本实验以齐墩果酸和熊果酸为对照品，建立了乌梅

熊果酸及五环三萜同类物的研究进展

湖南工业大学学报Journal of Hunan University of Technology Vol.23 No.5Sep.2009 第23卷 第5期2009年9月熊果酸及五环三萜同类物的研究进展 李宏杨１，刘国民１，刘 飞２，张凤琴２，李小龙２ （1. 海南大学 农学院，海南海口570228；2. 湖南工业大学包装与材料工程学院，湖南株洲412007） 摘要：五环三萜类化合物种类繁多，广泛分布在植物体中，且大多具有重要的药理活性，临床应用前景 十分诱人。随着研究的不断深入，有关五环三萜结构与活性的研究取得了大量进展，新的同类化合物不断的被发现。就熊果酸及五环三萜同类物结构与分类、在植物中的分布情况和药理作用的研究进展进行了综述。 关键词：熊果酸；五环三萜；抗肿瘤 中图分类号：Q541 文献标志码：A 文章编号：１６７３－９８３３（２００９）０５－００１８－０４ Research of Ursolic Acid and Similar Pentacyclic Triterpenoid Li Hongyang 1，Liu Guomin 1，Liu Fei 2，Zhang Fengqing 2，Li Xiaolong 2 （1. School of Agriculture ，Hainan University ，Haikou 570228，China ； 2. School of Packaging and Material Engineering ，Hunan University of Technology ，Zhuzhou Hunan 412007，China ） Abstract ：Various pentacyclic triterpenoids, widely distributing in plants, have excellent pharmacological activities. The clinical application of such compounds has attracted much attentions. The research of the structure and classification of Ursolic Acid and similar pentacyclic triterpenoids and their distribution and pharmacological functions are summarized. Keywords ：ursolic Acid ；pentacyclic triterpenoid ；antitumor 收稿日期：2009－08－17 基金项目：国家科技支撑计划子课题（2007BAD76B05－02）作者简介：李宏杨（1983－），男，河南信阳人，海南大学硕士研究生，主要研究方向为作物种质资源的创新与利用，E-mail ：hyang896@https://www.wendangku.net/doc/5d18461260.html, ；刘国民（1955－），男，湖南祁东人，海南大学教授，博士生导师，主要研究方向为作物种质资源的创新与利用，E-mail ：kudingcha_no1@https://www.wendangku.net/doc/5d18461260.html, 五环三萜类化合物是一类重要的天然产物，大多以游离形式或者与糖结合成苷的形式广泛存在于自然界中。熊果酸（ursolic acid ）又名乌索酸、乌苏酸，属于α－香树脂烷（α－amyrin ）型五环三萜类化合物。1990年，日本将熊果酸列为最有希望的癌化学预防药物之一[1]。大量研究表明，熊果酸及五环三萜同类物具有抗肿瘤、抗HIV 、抗糖尿病、抗菌、抗病毒、增强免疫功能和降血脂等多种生物学活性。近年来，国内外学者围绕熊果酸及五环三萜同类物的药理学作用、以及新五环三萜结构的发现做了大量的研究工作，取得了丰硕的成果，这些成果亦展示了五环三萜广泛的应用前景，为五环三萜的综合开发利用提供了可靠的实验依据。 １熊果酸及五环三萜同类物的结构 目前已发现的三萜类化合物多数为四环三萜和五 环三萜。五环三萜类成分在药用植物中较为常见，主要的结构类型有乌苏烷型、齐墩果烷型、羽扇豆烷型和木栓烷型等[2]，见图1。 乌苏烷（ursane ）型又称α－香树脂烷（α－amyrane ）型，如熊果酸、积雪草酸[3]、蔷薇酸[4]、坡模酸[5]、2α－羟基乌苏酸[6]；齐墩果烷（oleanane ）型又称(β－香树脂烷（β－amyrane ）型，如齐墩果酸、甘草酸、甘 草次酸[7]、丝石竹皂苷元[8]、蒲公英萜醇[9]、刺囊酸[10]等；羽扇豆烷（lupane ）型如白桦脂醇、白桦脂酸[11]、 与分类

熊果酸抗肿瘤作用机制的研究进展

Studies in Synthetic Chemistry 合成化学研究, 2016, 4(3), 19-27 Published Online September 2016 in Hans. https://www.wendangku.net/doc/5d18461260.html,/journal/ssc https://www.wendangku.net/doc/5d18461260.html,/10.12677/ssc.2016.43003 文章引用: 孟艳秋, 杨丽娜, 潘洪双, 于婷婷, 张伟晨, 宁梓廷. 熊果酸抗肿瘤作用机制的研究进展[J]. 合成化学研究, Research Progress on Antitumor Action Mechanism of Ursolic Acid Yanqiu Meng, Lina Yang, Hongshuang Pan, Tingting Yu, Weichen Zhang, Ziting Ning Shenyang University of Chemical Technology, Shenyang Liaoning Received: Oct. 1st , 2016; accepted: Oct. 16th , 2016; published: Oct. 21st , 2016 Copyright ? 2016 by authors and Hans Publishers Inc. This work is licensed under the Creative Commons Attribution International License (CC BY). https://www.wendangku.net/doc/5d18461260.html,/licenses/by/4.0/ Abstract Ursolic Acid is a type of pentacyclic triterpene compounds with many kinds of pharmacological ac-tivities, especially its antitumor activity. The antitumor mechanism of ursolic acid is multifaceted. In this paper, the research progress of anti-tumor mechanism of ursolic acid has been reviewed and forecasted. Keywords Ursolic Acid, Antitumor, Action Mechanism 熊果酸抗肿瘤作用机制的研究进展 孟艳秋，杨丽娜，潘洪双，于婷婷，张伟晨，宁梓廷 沈阳化工大学，辽宁 沈阳 收稿日期：2016年10月1日；录用日期：2016年10月16日；发布日期：2016年10月21日 摘 要 熊果酸是一种具有多种药理活性的五环三萜类化合物，其抗肿瘤活性尤为显著。熊果酸的抗肿瘤机制是多方面的。本文对熊果酸的抗肿瘤作用机制的研究进展进行综述并进行展望。 Open Access

熊果酸药理作用研究进展

熊果酸药理作用研究进展 ，相对分子量456 科植物毛子草的地上部分熊果酸具有广泛的 之 对致癌、促癌物有抵抗作用 多研究认为，熊果酸能通过化学预防、抗突变、细胞生长抑制和细胞毒等作用来抑制 到预防恶性肿瘤的目的。癌的发生、发展一般要经历始发突变、促癌和演变三阶段，干扰三个阶段即可达到延缓或阻止

显增加，部分细胞在

熊果酸在自然界中分布广泛，资源丰富，具有化学预防，保肝、抗肝炎，抗肿瘤、抗菌、抗病毒等多种药理活性，熊果酸药用开发景已被众多研究机构所重视，有望成为一种高效低毒的多用途新药。 【参考文献】 1 李开泉，陈武，熊筱娟，等.乌索酸的化学、药理及临床应用进展.中成药，2002， 2 4（9）:709-711. 2 Muto Y，Ninomiya M，Fujiki H.Present status of research on cancer chemopre vention in Japan.Jpn J Clin Oncol，1990，20（3）:219-221. 3 黄镜，孙燕.熊果酸的抗肿瘤活性.中国新药杂志，1997，6（2）:101-104. 4 Niikawa M，Hayashi H，Sato T，et al.Isolation of substances from glossy prive t（Ligustrum lucidum Ait）inhibiting the mutagenicity of benzo（α）preene in bacteri a.Mutat Res，1993，319（1）:1-4. 5 Young HS，Chung HY，Lee CK，et al.Ursolic acid inhibits aflatoxin B1-induced mutagenicity in a Salmonella assay system.Biol Pharm Bull，1994，17（7）:990-99 3. 6 Huang MT，Ho CT，Wang ZY，et al.Inhibition of skin tumorigenesis by rosema ry and its constituents carnosol and ursolic acid.Cancer Res，1994，54（3）:701-70 5. 7 Ohigashi H，Takamura H，Koshimizu K，et al.Search for possible an-titumor p romoters by inhibition of12-O-tetrade-canoylphorbol-13-acetate-induced Epstein-Barr v irus activation;ursolic acid and oleannolic acid from an anti-inflammatory Chinese m edicnal plant，Glechoma hederaceae L.Cancer Lett，1986，30（2）:143-148. 8 Ames BN.Dietary carcinogens and anticarcinogens.Science，1983，221:1256-12 58. 9 Balanehru S，Nagarajan B.Protective effect of oleanolic acid and urso-lic acid against lipid peroxidation.Biochem Int，1991，24（5）:981-984.

不同产地及外观形态夏枯草中齐墩果酸和熊果酸的含量比较

不同产地及外观形态夏枯草中齐墩果酸 和熊果酸的含量比较 （作者:___________单位: ___________邮编: ___________） 【摘要】目的比较不同产地、长度、色泽的夏枯草中齐墩果酸和熊果酸的含量，为更全面地控制夏枯草的质量提供依据。方法采用高效液相色谱法，以Shim Pack C18为色谱柱，乙腈甲醇水乙酸铵(体积比68∶16∶16∶0.5)为流动相，检测波长为215 nm，流速为0.8 mL/min。结果与结论不同产地夏枯草中齐墩果酸和熊果酸的含量差异较大，果穗短者两者含量高于果穗长者，紫红色果穗者两者含量高于棕色果穗。 【关键词】夏枯草产地果穗齐墩果酸熊果酸 Abstract:Objective To compare the contents of oleanolic acid and ursolic acid in Prunella vulgaris with different appearances and from different provenances,in order to control the quality of Prunella vulgaris.Methods Samples were analyzed on a Shim Pack C18 column. The mobile phase consisted of acetonitrile methol water ammonium acetate (68∶16∶16∶0.5)

under a flow rate of 0.8 mL·min-1. The detection wavelength was set at 215 nm.Results and Conclusions There were large differences in contents of oleanolic acid and ursolic acid among Prunella vulgaris with different provenances and appearances, higher in Prunella vulgaris with short and mauve ears. This method was suitable for the quality control of Prunella vulgaris. Key words:Prunella vulgaris;oleanolic acid;ursolic acid 夏枯草Prunella vulgaris为常用中药，以干燥果穗或全草入药，主要用于治疗目赤肿痛、头痛眩晕、瘰疬瘿瘤、乳痈肿痛、高血压等[1]。夏枯草中含有三萜及苷类、苯丙素类、黄酮类等多种化学成分，其中齐墩果酸和熊果酸是主要活性成分[2,3]。目前文献报道有采用衍生化气相色谱法、毛细管胶束电动色谱法、高效液相色谱法等方法评价夏枯草的质量[4-6]，但对于不同产地、长度、色泽的夏枯草中这两种三萜酸的含量比较还未见报道。本文以高效液相色谱法测定并比较不同产地、长度、色泽夏枯草样品中齐墩果酸及熊果酸的含量，旨在为更全面控制夏枯草的内在质量提供依据。 1 仪器与试药 Agilent 1100高效液相色谱仪：包括G1313A自动进样器，Agilent ChemStations数据处理软件，美国安捷伦科技有限公司;齐墩果酸对照品、熊果酸对照品：中国药品生物制品检定所，批号分别为110709200304、110742200516;乙腈：色谱纯，美国TEDIA公司;甲醇：分析纯及色谱纯，江苏汉邦科技有限公司;石油醚、乙酸铵：

熊果酸的功效与作用

熊果酸是由天然植物中的一种三萜类化合物而来，具特殊的气味，是存在于天然植物中的一种五环三萜类化合物。那么熊果酸具体有哪些的作用与功效呢？下边不妨一起来简单了解一下吧。 一、熊果酸的作用及功效 据临床医学表示，熊果酸中有的有益分子，非常显著而迅速的可以降低谷丙转氨酶、血清转氨酶等，对于消退小儿黄疽以及增进食欲等方面都有很好的促进，而对于抗纤维化和恢复肝功能症状，效果也非常的明显，而且还特别的稳定。熊果酸还具备有非常明显的抗氧化功效，这也使得它成为医药及化妆品方面的常备原料，例如医药方面对于肝部的治疗非常有益，能够保护并稳定稳定肝细胞膜、细胞器，从而使输出、运输等功能相继慢慢的恢复，在化妆品方面，由于熊果酸有很好的抗氧化作用，能使肌肤具有抵抗力，与此同时还有效淡化皱纹、修肌肤等皮肤难题。且熊果酸其实还是一味天然的保湿剂，大病可以调理，小病可以医治，又给人们带来不少的惊喜。

二、含量测定标准 1、色谱条件： 硅胶G薄层板;环己烷-氯仿-乙酸乙酯(20:5:8)为展开剂，上行展开;展距12～18cm;5%硫酸乙醇溶液，110℃加热5min显色。 2、样品溶液的制备： 精密称取栀子粉碎样品20g (炒栀子按得率折合后称取)，置索氏提取器内，加乙醚300ml回流提取至无色，回收溶剂至干，残留物加石油醚浸泡2次，每次15ml，约浸泡2min，倾去石油醚，用无水乙醇-乙醚(2：3)混合液微热使溶解并定容于5ml量瓶中，作为样品溶液。 3、对照品溶液的配制： 精密称取熊果酸对照品适量，加无水乙醇：乙醇(3：2)的混合溶液制成每毫升含1mg的溶液，作为对照品溶液。 4、测定： 准确吸取样品溶液及对照品溶液2μl，点于同一薄层板上。按上述色谱条件展开，显色。照薄层扫描法扫描，λS=520nm，λR=700nm;双波长反射法锯齿

齐墩果酸与熊果酸结构修饰物的药理活性和构效关系研究进展_刘丹

齐墩果酸与熊果酸结构修饰物的药理活性和构效关系研究进展 刘丹1,2　孟艳秋23　赵娟2 (1天津大学药物科学与技术学院　天津　300072;　2沈阳化工学院制药工程教研室　沈阳　110142) 刘丹　女,35岁,副教授,主要从事天然活性成分的结构修饰和医药中间体的合成工作。　3联系人,E 2mail :myq6581@https://www.wendangku.net/doc/5d18461260.html, 辽宁省自然科学基金资助项目(20042009) 2005-12-12收稿,2006-08-15收稿 摘　要　齐墩果酸(OA )和熊果酸(UA )均属于五环三萜类化合物,广泛存在于自然界中,具有多种显著的 生物活性。本文综述了近年来齐墩果酸及熊果酸结构修饰物的药理活性和构效关系的研究进展。 关键词　齐墩果酸　熊果酸　结构修饰　药理活性 R ecent Advance in the Study on Derivatives of Oleanolic Acid and U rsolic Acid Liu Dan 1,2,Meng Y anqiu 23,Zhao Juan 2(1C ollege of Pharmaceuticals &Biotechnology ,T ianjin University ,T ianjin 300072;2Faculty of Pharmaceutical Engineering ,Shenyang Institute of Chemical T echnology ,Shenyang 110142) Abstract Oleanolic acid and urs olic acid belong to triterpene acids which having numerous pharmacological activities and widely presenting in food ,medicinal herbs and other plants.Here a brief introduction of the recent progresses on pharmacological activities and the structure-activity relationship of derivatives of olean olic acid and urs olic acid are given out. K ey w ords Oleanolic acid ,Urs olic acid ,M odification ,Pharmacological activities 齐墩果酸(oleanolic acid ,OA ,1)和熊果酸(urs olic acid ,UA ,2)为结构类似物,均属于五环三萜类化合物,在自然界分布十分广泛,且具有多种生物活性。为了寻找高效低毒的衍生物,需对齐墩果酸和熊果酸的作用机制进行深入的研究;通过对32位羟基,C 122C 13位双键和282位羧基等官能团的结构修饰合成了一系列衍生物,进行了相关的药理活性测试,并与母体进行比较,获得了相应的构效关系。本文将就齐墩果酸及熊果酸结构修饰物的药理活性和构效关系研究进展进行综述。 1　 齐墩果酸及熊果酸化学及药理活性简介 齐墩果酸(C 30H 48O 3)属于β-香树脂醇型五环三萜类化合物,据不完全统计,它以游离形式或与糖结合的形式存在于大约60个科190种植物中[1],具有保肝[2,3]、消炎[4]、降糖[5]、抗HI V [6,7]和抗肿瘤[8～10]等药理作用。 熊果酸(C 30H 48O 3)为α-香树脂醇型五环三萜类化合物,以游离形式或与糖结合的形式存在于大约

熊果酸

打开的谱图文件：D:\10\熊果酸标准品3(00001).hw ───────────────────────────序号 保留时间 名称 峰面积% 峰面积 ─────────────────────────── 1 0.20 2 0.00464 3 118 2 0.23 3 0.001742 44 3 0.278 0.002292 58 4 0.444 0.009194 233 5 0.652 0.006404 163 6 0.922 0.006128 156 7 1.150 0.005266 134 8 1.199 0.002263 57 9 1.236 0.002975 76 10 1.453 0.009436 240 11 1.652 0.0075 190 12 1.803 0.001693 43 13 2.070 1.414 35901 14 2.659 0.09665 2454 15 2.777 0.1092 2773 16 3.084 1.454 36908 17 3.726 1.346 34185 18 4.277 0.2177 5529 19 4.675 0.4557 11571 20 4.886 0.322 8176 21 5.498 93.84 2382895 22 7.284 0.02985 758 23 7.588 0.006965 177 24 7.853 0.003855 98 25 8.058 0.01011 257 26 8.294 0.0007985 20 27 8.404 0.002138 54 28 8.594 0.00232 59 29 8.920 0.006411 163 30 9.097 0.003013 77 31 9.357 0.005584 142

熊果酸及五环三萜同类物的研究进展

熊果酸及五环三萜同类物的研究进展 李宏杨1，刘国民1，刘飞2，张凤琴2，李小龙2 (1. 海南大学农学院，海南海口570228 ；2. 湖南工业大学包装与材料工程学院，湖 南株洲412007) 摘要：五环三萜类化合物种类繁多，广泛分布在植物体中，且大多具有重要的药理活性，临床应用前景十分诱人。随着研究的不断深入，有关五环三萜结构与活性的研究取得了大量进展，新的同类化合物不断的被发现。就熊果酸及五环三萜同类物结构与分类、在植物中的分布情况和药理作用的研究进展进行了综述。 关键词：熊果酸；五环三萜；抗肿瘤 五环三萜类化合物是一类重要的天然产物，大多以游离形式或者与糖结合成苷的形式广泛存在于自然界中。熊果酸(ursolic acid) 又名乌索酸、乌苏酸，属于oc 一香树脂烷(r,-amyrin) 型五环三萜类化合物。1990 年，日本将熊果酸列为最有希望的癌化学预防药物之一。大量研究表明，熊果酸及五环三萜同类物具有抗肿瘤、抗HIV、抗糖尿病、抗菌、抗病毒、增强 免疫功能和降血脂等多种生物学活性。近年来，国内外学者围绕熊果酸及五环三萜同类物的药理学作用、以及新五环三萜结构的发现做了大量的研究工作，取得了丰硕的成果，这些成果亦展示了五环三萜广泛的应用前景，为五环三萜的综合开发利用提供了可靠的实验依据。 1 熊果酸及五环三萜同类物的结构与分类 目前已发现的三萜类化合物多数为四环三萜和五环三萜。五环三萜类成分在药用植物中较为常见，主要的结构类型有乌苏烷型、齐墩果烷型、羽扇豆烷型和木栓烷型等，见图1。 乌苏烷(Ill'Sane) 型又称一香树脂烷(r,-amyrane) 型，如熊果酸、积雪草酸、蔷薇酸引、坡模酸I 、2 一羟基乌苏酸：齐墩果烷(oleanane) 型又称( 口一香树脂烷(B-amyrane) 型，如齐墩果酸、甘草酸、甘草次酸、丝石竹皂苷元引、蒲公英萜醇、刺囊酸等；羽扇豆烷(1upane)型如白桦脂醇、白桦脂酸n”羽扇豆醇、乙酸羽扇豆醇酯ml等；木栓烷(friedeiane) 型如木栓酮㈣、雷公藤红素、demethylzeylasteral 、salaspermic acid 、2,3 — dihydroxy-friedel-6 ，9(1 1) 一en 一29-oic acid 等。 2 熊果酸及五环三萜同类物在植物中的分布 据不完全统计，在自然界已有34科108种植物中能分离得到熊果酸，主要分布在女贞子、山楂、珍珠菜、夏枯草、车前草、甘草、连翘和苦丁茶等药用植物中。齐墩果酸是一种齐墩果烷型五环三萜类化合物，广泛分布于约60 科190种植物中，如：青叶胆全草、白花蛇舌草、女贞果实等，以游离形式或与糖结合成苷存在。就冬青科苦丁茶而言，目前发现含量 最丰富的五环三萜类化合物是熊果酸和齐墩果酸，主要存在于苦丁茶冬青、大叶冬青的枸骨嫩芽和功能叶之中。除此之外，冬青科苦丁茶中尚含有若干种含量较低的其它五环三萜类化合物。人们在大叶冬青中分离鉴定了 1 3 种新型三萜皂苷和7 种三萜苷元；在苦丁茶冬青

介孔材料合成方法

三维介孔材料SBA-16的制备 分别称取12 g F108和31.44 g硫酸钾放入500 mL烧杯中，加入360 g浓度为2 M的盐酸。在室温下（25 °C）搅拌4 h，使表面活性剂全部溶解并且分散均匀后，将温度升至38 °C。待恒温后，在剧烈搅拌下，逐滴加入25.2 g正硅酸乙酯（TEOS），连续搅拌20 min后停止。静置保持反应物24 h，整个过程维持38 °C 不变。所得白色粉末，通过离心进行收集（转速5000 rpm）,用去离子水洗涤6次，并在烘箱中40 °C干燥。表面活性剂在500 °C空气中焙烧5 h去除，升温速度控制在2 °C /min。 二维介孔二氧化硅材料SBA-15的制备 室温下，将1 g P123和2.24 g KCl溶于30 g 2 M的盐酸中，当搅拌至均一溶液后，逐滴加入2.08 g正硅酸乙酯（TEOS）,并强烈搅拌30 min。静置24 h 后，把所得混合物转移至带聚四氟乙烯衬套的不锈钢反应釜中，100 °C晶化24 h。自然冷却后，经抽滤，反复洗涤，在烘箱中过夜烘干。 三维介孔二氧化硅材料SBA-16的制备 在45 °C下，将4.0 g F127和8.0 g浓盐酸（37 wt%）溶于192 g蒸馏水中。在搅拌均一后，加入12.0 g 正丁醇，并强烈搅拌1 h。逐滴加入18 g正硅酸乙酯（TEOS）后，在相同温度下搅拌24 h。将所得混合物转移至带聚四氟乙烯衬套的不锈钢反应釜中，100°C晶化24 h。自然冷却，经抽滤，反复洗涤，所得粉末样品在烘箱中过夜烘干。 MCM-41的合成 将4.38 g CTAB加入到含1.10 g NaOH的200 g蒸馏水中。室温搅拌使其完全溶解，逐滴加入5.21 g TEOS，并继续搅拌24 h。将混合物转移至带有聚四氟乙烯内衬的反应釜中，在110 °C条件下晶化24 h。所得产物抽滤后，用蒸馏水反复冲洗直至滤液呈中性，将产物干燥。 介孔二氧化硅分子筛KIT-6的制备

熊果酸的生物活性及其研究热点

2010年第卷第期 137[收稿日期]2010-05-14 [作者简介]刘柯彤（1988-），陕西榆林人，陕西理工学院化学工程与工艺专业2008级本科生。摘要：综述了近年来熊果酸生物活性的研究进展，重点讨论了其研究热点，展望了其今后的发展趋势。 关键词：熊果酸；生物活性；研究热点 中图分类号：O624 文献标识码：A doi ：10.3969/j.issn.1007-7871.2010.07.002 熊果酸的生物活性及其研究热点 刘柯彤，陶亮亮，马雄，刘军海 （陕西理工学院化学与环境科学学院，陕西汉中723001） 0前言熊果酸（Ursolic Acid ，UA ），又名乌索酸、乌苏酸，属α-香树脂醇型五环三萜类化合物。纯净的熊果酸为白色针状晶体，熔点为285~287℃，易溶于二氧六环吡啶，可溶于甲醇、乙醇，微溶于丙酮、苯、氯仿和乙醚。在自然界中熊果酸主要分布在女贞子、山楂、夏枯草、车前草和苦丁茶等多种植物中[1，2]。近年来，有关熊果酸的提取已经成为天然产物加工领域的研究热点之一；随着对熊果酸生物活性研究的深入，其在医药、食品、保健和化妆品等领域获得了广泛的应用。本文综述了熊果酸的提取工艺及其生物活性的研究进展，重点讨论了研究的热点问题及发展趋势，以期为熊果酸进一步的开发利用提供参考。1熊果酸的生物活性熊果酸具有广泛的生物活性，尤其在抗肿瘤、抗氧化、抗菌抗病毒、保肝和美容护肤等方面的作用显著，值得重视。1.1抗肿瘤作用研究发现，熊果酸具有抗致癌、抗促癌、诱导F9畸胎瘤细胞分化和抗肿瘤血管形成的作用。其主要通过以下几方面进行作用：熊果酸能抗突变、抑制癌变的启动、能直接杀伤肿瘤细胞，具有肿瘤逆转作用及抗侵袭性、诱导肿瘤细胞凋亡和抑制肿瘤血管形成，从而抑制癌变的形成；并且对多种肿瘤细胞体内、外均有抑制作用，并可 以减少放疗、化疗之后对造血系统的损害[3]。熊果酸对结肠癌、黑色素瘤和胃癌等多种细胞系具有抑制作用，并诱导其凋亡，其机制可能是通过影响细胞周期及癌相关基因的表达而实现的[4]。于丽波等研究发现熊果酸可明显抑制卵巢癌细胞生长，并诱导细胞凋亡，其主要机制与调节Bcl-2和Bax 的蛋白表达有关[5]。刘琼等研究表明， 熊果酸具有抑制恶性胶质瘤裸鼠移植瘤生长的作用，其机制可能与下调ERK1、C -Jun 、C -Myc 、CyclinD1表达有关[6]。 1.2抗氧化作用 氧化作用是造成人类衰老现象的重要原因之一，在防止人体内不良胆固醇（LDL ）的氧化，保持血管的年轻化方面，熊果酸扮演着重要角色。 熊果酸具有明显的抗氧化功能，因而被广泛 地用作医药和化妆品原料。抗氧化作用对人体抗 衰老和皮肤祛斑、祛色素、美容都有积极作用。 对于熊果酸的抗氧化作用有人曾作过研究，如卢静等采用邻苯三酚自氧化法，Feton 体系法测定熊果酸对超氧阴离子和羟自由基的清除能力，从而 探究熊果酸的抗氧化性能。结果表明熊果酸对超 氧阴离子和羟自由基有明显的清除作用，对超氧 阴离子的最高清除率可达88.42%，但是清除作用弱于同浓度下的VC 。熊果酸对羟自由基的清除作用最高可达86.35%，并且强于同浓度下的甘露醇，具有明显的抗氧化性[7]。王建梅等研究发现，熊果酸有保护糖尿病大鼠血管损伤的作用，机制可能 Surveys &Reviews 综述与述评 11

熊果酸的研究进展

作者：肖坤福郑云法刘成左张春牛 【关键词】熊果酸；,,,检测方法；,,,提取方法；,,,动物实验；,,,临床研究熊果酸是广泛存在于白花蛇舌草、女贞子、乌梅、夏枯草等天然植物中的一种五环三萜类化合物，有研究表明熊果酸具有镇静、抗炎、抗菌、抗糖尿病、降血糖等多种生物学效应，早在1996年，日本学者神藏美枝子等人从杜鹃花科越桔属植物越桔叶中提取了具有较高熊果酸浓度的熊果酸产品，产品中除含有25%的熊果酸外，尚含有大量的熊果酸衍生物、熊果苷和其它三萜类化合物等，具有多种活性成分，用于增强机体免疫力、预防心血管系统疾病、稳定肝功能等。现在人们对其研究越来越多，并在很多方面取得了可喜的研究进展。 1 提取方法 对三萜类化合物的分离提纯是其研究起点，没有较好的提取工艺，就更谈不上对其进一步研究。近年来，许多科研工作者在这方面做出了突出的贡献。有些科研工作者［1～5］，通过正交实验确定85%～95%的乙醇提取熊果酸效果最佳。崔星明等［6］采用超临界流体萃取得到的芦笋提取物，用甲醇溶解，采用液相色谱-质谱联用仪检测，得到了56个组分。发现有保留时间和熊果酸基本一致的峰。其质谱分子离子峰和特征碎片峰都与熊果酸的一致，确定该化合物为熊果酸。 2 检测方法 在检测方法方面，有不少科研工作者对其进行了较深入的研究。熊慧敏［7］全面地论证了薄层层析-双波长扫描法测定大山楂咀嚼片中熊果酸含量的检测限的线性范围可行性，并考查了此方法的测定熊果酸的稳定性和重复性，从而证明薄层层析-双波长扫描法测定熊果酸精密度、稳定性、重现性、回收率均都达有关规定的要求，本方法操作简单方便，结果可靠，可作为检验产品质量的一个快速而实用的定量方法。朱玉琴等［8］在采用薄层扫描检测保驾胶囊中熊果酸的含量时首次对显色剂进行了改进，并验证了醋酸-浓硫酸 (9∶1)比10%硫酸乙醇显色要好，检测限低等优点。与此同时，杨云等［9］在采用薄层层析检测牙周康泰胶囊熊果酸的含量验证了10%磷钼酸乙醇液比10%硫酸乙醇显色要好。 罗启剑等［10］采用分光光度法测定连钱草中熊果酸含量。郭艳玲等［11］和陈志强［12］采用薄层扫描法分别测定了补肾颗粒和消食贴中熊果酸含量，方法简便、快速、准确，可作为该产品的质量控制方法。 周静等［13］探求用毛细管气相色谱法测定女贞子中齐墩果酸和熊果酸含量。取女贞子氯仿提取液自然挥发干，甲醇溶解经甲酯化后，进样分析。色谱条件：hp－1毛细管柱（25 cm×0.32 mm，0.52 μm），柱温280℃，氮气为载气，氢火焰检测器。分析结果表明熊果酸的线性良好，回收率为99.8%±2.1%。所建立的气相色谱法可以作为女贞子药材的质量检测方法。 施慧君等［14］采用hplc法测定知柏地黄冲剂中熊果酸的含量。选用ods-c：色谱柱，流动相：甲醇-水(99∶1)，磷酸调ph 2.5，检测波长：206 nm，流速：1.2 ml/min，柱温25℃的条件下，熊果酸线性关系良好(r=0.999 8) 平均回收率达98.7%(rsd=0.66%)。罗晓清等［15］采用rp-hplc法测定石精叶中熊果酸含量，色谱柱为zorbax ods柱，用甲醇（1%），醋酸水溶液(88∶12)为流动相。检测波长为215nm。结果熊果酸和齐墩果酸的平均收率分别为98.5%、97.6%(n=3)。rsd分别为1.62%，1.89%(n=3)。方法准确、灵教、快速，可作为石抽叶药材的质量检测方法之一。 杨书良等［16］采用高效液相色谱法从影响熊果酸测定的各个方面(例如：粒度、煎煮次数、溶媒量、提取时间等)进行测定和和正交分析，从而论证了它比薄层层析法更精确、更可靠、灵敏度更高，重现性更好。鞠建华等［17］，也采用高效液相色谱测定熊果酸含量，但他在前人的基础上调节流动相的比例和加入改性剂乙酸胺，验证了此改进方法可以使熊果酸和它的同分异构体齐墩果酸达到基线分离，并使基线平稳、峰型和分离效果较佳。鄢立新等