Effect of Sheng-Jiang Powder on Gut Microbiota in High-Fat Diet-Induced NAFLD.

BACKGROUND AND AIMS: Nonalcoholic fatty liver disease (NAFLD) is an alarming global health problem that is predicted to be the major cause of cirrhosis, hepatocellular carcinoma, and liver transplantation by next decade. Gut microbiota have been revealed playing an important role in the pathogenesis of NAFLD. Sheng-Jiang Powder (SJP), an empirical Chinese medicine formula to treat NAFLD, showed great hepatoprotective properties, but the impact on gut microbiota has never been identified. Therefore, we performed this study to investigate the effect of SJP on gut microbiota in NAFLD mice. METHODS: NAFLD was induced by 12 weeks' high-fat diet (HFD) feeding. Mice were treated with SJP/normal saline daily for 6 weeks. Blood samples were obtained for serum biochemical indices and inflammatory cytokines measurement. Liver tissues were obtained for pathological evaluation and oil red O staining. The expression of lipid metabolism-related genes was quantified by RT-PCR and Western blotting. Changes in gut microbiota composition were analyzed by the 16s rDNA sequencing technique. RESULTS: HFD feeding induced significant increase in bodyweight and serum levels of TG, TC, ALT, and AST. The pathological examination revealed obvious hepatic steatosis in HFD feeding mice. Coadministration of SJP effectively protected against bodyweight increase and lipid accumulation in blood and liver. Increased expression of PPARγ mRNA was observed in HFD feeding mice, but a steady elevation of PPARγ protein level was only found in SJP-treated mice. Meanwhile, the expression of FASN was much higher in HFD feeding mice. Microbiome analysis revealed obvious changes in gut microbiota composition among diverse groups. SJP treatment modulated the relative abundance of short-chain fatty acids (SCFAs) producing bacteria, including norank-f-Erysipelotrichaceae and Roseburia. CONCLUSIONS: SJP is efficient in attenuating HFD-induced NAFLD, and it might be partly attributed to the regulation of gut microbiota.

Effect of Different-Volume Fluid Resuscitation on Organ Functions in Severe Acute Pancreatitis and Therapeutic Effect of Poria cocos.

OBJECTIVE: To explore the effect of different-volume fluid resuscitation (FR) on organ functions in severe acute pancreatitis (SAP) and to elucidate the therapeutic effect and mechanism of Poria cocos on organ injuries caused by high-volume FR. METHODS: 1. Clinical study: retrospective analysis of thirty-one patients about the effect of titrated fluid resuscitation protocol (TFR) on the occurrence of acute kidney injury (AKI) secondary to SAP. 2. Experimental study: rats (N = 30) were randomly divided into five groups: sham, model, low-volume FR (1.5 ml/kg/h), high-volume FR (10 ml/kg/h), and Poria cocos combined with high-volume FR (10 ml/kg/h + intraintestinal administration Poria cocos 5 g/kg); serum or plasma indicators and histopathologic scores were compared to explore the effect and mechanism of different fluid volumes and Poria cocos on organ function in SAP. RESULTS: The occurrence of AKI, fluid volume, and fluid velocity in TFR group was lower than that in the control group. Logistic regression analysis showed that increased Marshall scores and fluid velocity were risk factors for predicting occurrence of AKI in SAP. Low-volume FR decreased the levels of blood urea nitrogen (BUN), serum creatinine (Cr), matrix metalloproteinase (MMP), and pathologic scores of the pancreas and kidney. High-volume FR increased ascites, MMPs, and kidney pathologic scores. Poria cocos decreased the levels of BUN, Cr, MMPs, and pathologic scores of the pancreas and kidney and increased the arterial oxygen saturation. CONCLUSION: TFR-associated lower fluid volume and velocity reduced the occurrence of AKI secondary to SAP. High volume might aggravate AKI via increased MMP release leading to endothelial glycocalyx damage and vascular endothelial dysfunction. Poria cocos reduced MMP release, relieved glycocalyx damage, and alleviated the pancreas and kidney injury aggravated by high fluid volume in SAP. Therefore, endothelial glycocalyx protection might be a new strategy in the treatment of SAP.

Optimal timing for the oral administration of Da-Cheng-Qi decoction based on the pharmacokinetic and pharmacodynamic targeting of the pancreas in rats with acute pancreatitis.

AIM: To identify the optimal oral dosing time of Da-Cheng-Qi decoction (DCQD) in rats with acute pancreatitis (AP) based on the pharmacokinetic and pharmacodynamic parameters. METHODS: First, 24 male Sprague-Dawley rats were divided into a sham-operated group [NG(a)] and three model groups [4hG(a), 12hG(a) and 24hG(a)]. The NG(a) and model groups were administered DCQD (10 g/kg.BW) intragastrically at 4 h, 4 h, 12 h and 24 h, respectively, after AP models induced by 3% sodium taurocholate. Plasma samples were collected from the tails at 10 min, 20 min, 40 min, 1 h, 2 h, 4 h, 8 h, 12 h and 24 h after a single dosing with DCQD. Plasma and pancreatic tissue concentrations of the major components of DCQD were determined by high-performance liquid chromatography tandem mass spectroscopy. The pharmacokinetic parameters and serum amylase were detected and compared. Second, rats were divided into a sham-operated group [NG(b)] and three treatment groups [4hG(b), 12hG(b) and 24hG(b)] with three corresponding control groups [MG(b)s]. Blood and pancreatic tissues were collected 24 h after a single dosing with DCQD. Serum amylase, inflammatory cytokines and pathological scores of pancreatic tissues were detected and compared. RESULTS: The concentrations of emodin, naringin, honokiol, naringenin, aloe-emodin, chrysophanol and rheochrysidin in the 12hG(a) group were higher than those in the 4hG(a) group in the pancreatic tissues (P < 0.05). The area under the plasma concentration-time curve from time 0 to the time of the last measurable concentration values (AUC0→t) for rhein, chrysophanol, magnolol and naringin in the 12hG(a) group were larger than those in the 4hG(a) or 24hG(a) groups. The 12hG(a) group had a higher Cmax than the other two model groups. The IL-10 levels in the 12hG(b) and 24hG(b) groups were higher than in the MG(b)s (96.55 ± 7.84 vs 77.46 ± 7.42, 251.22 ± 16.15 vs 99.72 ± 4.7 respectively, P < 0.05), while in the 24hG(b) group, the IL-10 level was higher than in the other two treatment groups (251.22 ± 16.15 vs 154.41 ± 12.09/96.55 ± 7.84, P < 0.05). The IL-6 levels displayed a decrease in the 4hG(b) and 12hG(b) groups compared to the MG(b)s (89.99 ± 4.61 vs 147.91 ± 4.36, 90.82 ± 5.34 vs 171.44 ± 13.43, P < 0.05). CONCLUSION: Late-time dosing may have higher concentrations of the most major components of DCQD, with better pharmacokinetics and pharmacodynamics of anti-inflammation than early-time dosing, which showed the late time to be the optimal dosing time of DCQD for AP.

Pharmacokinetics and pharmacodynamics of Da-Cheng-Qi decoction in the liver of rats with severe acute pancreatitis.

AIM: To explore the pharmacokinetics and pharmacodynamics of Da-Cheng-Qi decoction (DCQD) in the liver of rats with severe acute pancreatitis (SAP) based on an herbal recipe tissue pharmacology hypothesis. METHODS: Healthy male Sprague-Dawley rats were randomly divided into a sham operation group (SOG); a model group (MG); and low-, median- and high-dose treatment groups (LDG, MDG, and HDG, respectively). Different dosages (6, 12 and 24 g/kg for the LDG, MDG, and HDG, respectively) of DCQD were administered to the rats with SAP. The tissue concentrations of aloe-emodin, rhein, emodin, chrysophanol, honokiol, rheo chrysophanol, magnolol, hesperidin, naringenin and naringin in the liver of the treated rats were detected by high-performance liquid chromatography tandem mass spectrometry. Alanine transaminase (ALT) and aspartate transaminase (AST) in serum, inflammatory mediators in the liver and pathological scores were evaluated. RESULTS: The major components of DCQD were detected in the liver, and their concentrations increased dose-dependently. The high dose of DCQD showed a maximal effect in ameliorating the pathological damages, decreasing the pro-inflammatory mediators tumor necrosis factor-α and interleukin (IL)-6 and increasing anti-inflammatory mediators IL-4 and IL-10 in the liver. The pathological scores in the pancreas for the MG were significantly higher than those for the SOG (P < 0.05). DCQD could reduce the pathological scores in the pancreas and liver of the rats with SAP, especially in the HDG. Compared to the SOG, the ALT and AST levels in serum were higher in the MG (P < 0.05), while there was no statistical difference in the MG and HDG. CONCLUSION: DCQD could alleviate liver damage by altering the inflammatory response in rats with SAP based on the liver distribution of its components.

Effect of acute pancreatitis on the pharmacokinetics of Chinese herbal micron Liuhe Pill ointment in rats.

OBJECTIVE: To explore the effect of acute pancreatitis (AP) on the pharmacokinetics of herbal ointment micron Liuhe Pill, MLHP) components in anesthetized rats. METHODS: Rats were randomly divided into a AP model group (n=6) and a normal group as a control (n=6). The rat model of AP was induced by intraperitoneal injection of L-arginine in rats (15 mg/kg, twice, interval 1 h). Chinese herbal ointment MLHP was used externally on the belly after the 2nd injection for 48 h in both groups. Emodin, rhein, aloe emodin, physcion, chrysophanol from MLHP were detected and quantified in rat serum and pancreas (at 48 h) by high performance liquid chromatography-tandem mass spectrometry. RESULTS: Among the five components, only emodin, aloe emodin and physcion from MLHP were detected in all rat serum and most of the rats' pancreas. Rhein and chrysophanol were not detected in both serum and pancreas. T1/2α of emodin and physcion in MLHP were obviously shorter in the AP model group than those in the normal group (P<0.05), while there was no difference for T1/2α of aloe emodin. The peak concentration and area under curve of all three components were much higher in the AP group than those in the normal group with MLHP in external application for 48 h (P<0.05). Furthermore, the mean residence time (MRT) and maximum plasma concentration (Tmax) of emodin and aloe emodin were obviously longer in the AP model group than those in the normal control group (P<0.05). There was no significant difference for Ka of all components between the two groups. Emodin could be detected in all rats' pancreas at 48 h in both groups, while its mean pancreatic concentration was higher in the AP model group than in the normal group (0.61±0.54 ng/mL, 0.42±0.37 ng/mL, respectively,P<0.05). Aloe emodin could be detected in all rats' pancreas at 48 h in both groups and their mean pancreatic concentration were similar (0.31±0.24 ng/mL, 0.33±0.17 ng/mL, respectively,P>0.05). Physcion could be detected in pancreas of most rats in the AP model while only two rats in the normal group. CONCLUSION: AP could significantly affect the pharmacokinetics of absorbed components of Chinese herbal MLHP ointment in rats.

Metabolomic profiles illuminate the efficacy of Chinese herbal Da-Cheng-Qi decoction on acute pancreatitis in rats.

BACKGROUND AND OBJECTIVES: Chinese herbal drug Da-Cheng-Qi decoction (DCQD) has been widely used for decades to treat acute pancreatitis (AP). Previous trials are mostly designed to state the potential mechanisms of the therapeutic effects rather than to detect its whole effect on metabolism. This study aimed to investigate the efficacy of DCQD on metabolism in AP. METHODS: Twenty-two male adult Sprague-Dawley rats were randomized into three groups. AP was induced by retrograde ductal infusion of 3.5% sodium taurocholate solution in DCQD and AP group, while 0.9% saline solution was used in sham operation (SO) group. Blood samples were obtained 12 h after drug administration and a 600 MHz superconducting Nuclear Magnetic Resonance (NMR) spectrometer was used to detected plasma metabolites. Principal Components Analysis (PCA) and Partial Least Squares-Discriminant Analysis after Orthogonal Signal Correction (OSC-PLS-DA) were applied to analyze the Longitudinal Eddy-delay (LED) and Carr-Purcell-Meiboom-Gill (CPMG) spectra. RESULTS: Differences in concentrations of metabolites among the three groups were detected by OSC-PLS-DA of 1HNMR spectra (both LED and CPMG). Compared with SO group, DCQD group had higher levels of plasma glycerol, glutamic acid, low density lipoprotein (LDL), saturated fatty acid (FA) and lower levels of alanine and glutamine, while the metabolic changes were reversed in the AP group. CONCLUSIONS: Our results demonstrated that DCQD was capable of altering the changed concentrations of metabolites in rats with AP and 1HNMR-based metabolomic approach provided a new methodological cue for systematically investigating the efficacies and mechanisms of DCQD in treating AP.

Effect of electroacupuncture on the inflammatory response in patients with acute pancreatitis: an exploratory study.

OBJECTIVES: To examine the effects of electroacupuncture (EA) on inflammatory responses in patients with acute pancreatitis (AP). METHODS: Eighty patients with mild or severe AP were randomly allocated to a control group or an EA group. All patients were managed conservatively. In addition, the EA group received acupuncture for 30 min per day for 7 days at bilateral points ST36, LI4, TE6, ST37 and LR3. Interleukin (IL)-6, IL-10 and C-reactive protein (CRP) levels were measured on admission and on day 7. The time to re-feeding and length of stay in hospital were also recorded. RESULTS: A total of 58 patients provided complete data. The characteristics of the patients in the EA and control groups were similar. After 7 days the serum concentrations of IL-10 were higher in the EA group than in the control group (mild AP: 6.2±1.2 vs 5.2±0.9 pg/mL, p<0.05; severe AP: 14.9±7.8 vs 7.9±6.3 pg/mL, p<0.05). For patients with severe AP, the CRP level in the EA group was lower than in the control group (p<0.05). CONCLUSIONS: EA may reduce the severity of AP by inducing anti-inflammatory effects and reducing the time to re-feeding; however, it did not reduce the length of hospital stay. TRIAL REGISTRATION NUMBER: ChiCTR-TRC-13003572.

1HNMR-based metabolomic profile of rats with experimental acute pancreatitis.

BACKGROUND: Acute pancreatitis (AP) is a common inflammatory disease of the pancreas accompanied by serious metabolic disturbances. Nevertheless, the specific metabolic process of this disease is still unclear. Characterization of the metabolome may help identify biomarkers for AP. To identify potential biomarkers, this study therefore investigated the 1H-nuclear magnetic resonance (NMR)-based metabolomic profile of AP. METHODS: Fourteen male adult Sprague-Dawley rats were randomized into two groups: the AP group, in which AP was induced by retrograde ductal infusion of 3.5% sodium taurocholate; and the sham operation group (SO), in which rats were infused with 0.9% saline. Blood samples were obtained 12 hours later and a 600 MHz superconducting NMR spectrometer was used to detect plasma metabolites. Principal components analysis (PCA) and partial least squares-discriminant analysis after orthogonal signal correction (OSC-PLS-DA) were used to analyze both longitudinal Eddy-delay (LED) and Carr-Purcell-Meiboom-Gill (CPMG) spectra. RESULTS: Differences in plasma metabolites between the two groups were detected by PCA and PLS-DA of 1HNMR spectra. Compared with the SO group, plasma levels of lactate (δ 1.3, 1.34, 4.1), valine (δ 0.98, 1.02), succinic acid (δ 2.38), 3-hydroxybutyric acid (3-HB, δ 1.18), high density lipoprotein (HDL, δ 0.8), and unsaturated fatty acid (UFA, δ 2.78, 5.3) were elevated in the AP group, while levels of glycerol (δ 3.58, 3.66), choline (δ 3.22), trimethylamine oxide (TMAO, δ 3.26), glucose (δ 3-4), glycine (δ 3.54), very low density lipoprotein (VLDL, δ 1.34) and phosphatidylcholine (Ptd, δ 2.78) were decreased. CONCLUSIONS: AP has a characteristic metabolic profile. Lactate, valine, succinic acid, 3-HB, HDL, UFA, glycerol, choline, TMAO, glucose, glycine, VLDL, and Ptd may be potential biomarkers of early stage AP.

Electroacupuncture Ameliorates Acute Lung Injury through Promoting Gastrointestinal Motility in Rats with Acute Pancreatitis.

Objective. Gastrointestinal disfunction and acute lung injury (ALI) were common in acute pancreatitis (AP). The effect of electro-acupuncture (EA) on gastrointestinal motility and ALI in rats with AP was investigated to verify the theory of "lung and large intestine are interior exteriorly related" in traditional Chinese medicine. Methods. Male Sprague-Dawley rats were randomly divided into the normal group, model group, and EA group. AP model was established by three injections of 20% L-arginine at 1 h intervals. EA were applied to bilateral ST-25 and ST-36 for 30 minutes twice a day after modeling for 3 days. Arterial blood, pancreas, lung, and intestinal tissues were collected for detecting the inflammatory factors and histopathology. Intestinal propulsion rate (IPR) was also measured at 72 h. Results. EA treatment improved IPR and increased CCK-8 level compared with model group (P < 0.05). It lowered the serum levels of TNF- α and IL-6 and increased the level of IL-4 with no effect on IL-10. EA treatment reduced serum vasoactive intestinal peptide (VIP) and myeloperoxidase (MPO) level in the lung and the pathologic scores of pancreas, lung and intestine were decreased (P < 0.05). Conclusion. EA treatment could promote gastrointestinal motility through inhibiting VIP, and promoting CCK expression and regulate pro- and anti-inflammatory mediators to ameliorate ALI in AP.

Pharmacokinetic and pharmacodynamic comparison of chinese herbal ointment liu-he-dan and micron liu-he-dan ointment in rats with acute pancreatitis.

Aim. To compare the pharmacokinetics and pharmacodynamics of herbal ointment Liu-He-Dan (LHD) and micron LHD (MLHD) in rats with acute pancreatitis (AP). Methods. Twenty rats were allocated into normal, AP, LHD, and MLHD groups. LHD or MLHD was applied on rats' abdomens. Plasma levels of emodin, rhein, aloe emodin, physcion, and chrysophanol were determined by high performance liquid chromatography-mass spectrometry-mass spectrometry (HPLC-MS-MS) at different time points, and the pharmacokinetic parameters were calculated. Serum amylase, TNF- α , IL-6, and IL-10 levels, and the pancreatic pathological scores were determined at 48 h after LHD or MLHD treatment. Results. T 1/2 α and area under the curve (AUC) of emodin in the MLHD group were lower than those in the LHD group, while T 1/2 α and AUC of aloe emodin in the MLHD group were higher than those in the LHD group (P < 0.05). T 1/2 α and T max of physcion in the MLHD group were significantly shorter than those in the LHD group (P < 0.05). Compared with the AP group, the amylase, malondialdehyde (MDA), TNF- α , and IL-6 levels decreased significantly after three days of treatment in LHD and MLHD groups, while the levels of superoxide dismutase (SOD), TNF- α , and the pancreatic pathological score, were similar. The pharmacodynamic parameters between the LHD and MLHD groups were similar. Conclusion. MLHD had better pharmacokinetics than, and similar pharmacodynamics to, LHD in the management of rats with AP, which indicated that MLHD might be substituted for LHD in the treatment of AP and thus reduce the amount of medicinal herbs used.

Effect of acute pancreatitis on the pharmacokinetics of Chinese herbal ointment Liu-He-Dan in anaesthetized rats.

ETHNOPHARMACOLOGICAL RELEVANCE: Chinese herbal preparation of Liu-He-Dan ointment has been adapted for acute pancreatitis in external application for many years in West China. AIM OF THE STUDY: To investigate the effect of acute pancreatitis on the pharmacokinetics of Liu-He-Dan ointment in rats while it was used externally on belly. MATERIALS AND METHODS: Twelve male Sprague-Dawley rats were randomly divided into acute pancreatitis model group (n=6) and normal group as a control (n=6). Chinese herbal Liu-He-Dan ointment was used externally on belly. Emodin, rhein, aloe emodin, physcion and chrysophanol in plasma and pancreas (at 48 h) were detected and quantified by liquid chromatography-tandem mass spectrometry. Amylase in plasma were determined with iodide process. RESULTS: Among the five components, only emodin, aloe emodin and physcion from Liu-He-Dan were detected in plasma and pancreas. The absorption of each component was tended to decrease in acute pancreatitis group after topically management with Liu-He-Dan ointment on rats' abdomen. The T(max), C(max) and area under curve (AUC) of each component were distinctly lower in AP group than those in normal group (p<0.05). However, the T(1/2α) and mean retention time (MRT) of emodin lasted longer in acute pancreatitis group than those in normal group (p<0.05). There was no statistical difference in the MRT of aloe emodin and physcion between the two groups. Emodin could be detected in all rats' pancreas at 48 h in both groups, while its mean pancreatic concentration was higher in acute pancreatitis model group than in normal group (0.91 ± 0.68, 0.41 ± 0.36, respectively). Physcion could be detected in pancreas of most acute pancreatitis models, but not in normal rats. Aloe emodin was found in all pancreas from acute pancreatitis models while only one in normal group. The level of amylase in Liu-He-Dan group was obviously lower than that in the AP model group (p=0.0055). CONCLUSION: We concluded that acute pancreatitis may significantly affect the pharmacokinetics of Liu-He-Dan while external applied on belly, which indicated the dosage modification in AP. However, acute pancreatitis seems to promote the distribution of the detected components into pancreas. The ointment could help relieve the disease of pancreatitis.

Early oral refeeding wisdom in patients with mild acute pancreatitis.

OBJECTIVES: To evaluate the safety and efficacy of early oral refeeding (EORF) in patients with mild acute pancreatitis (AP) and to investigate the optimal duration to commence EORF. METHODS: A prospective, randomized, controlled trial was conducted in patients with mild AP. Patients with EORF (started oral feeding once they subjectively felt hungry) were compared with patients receiving routine oral refeeding (RORF) for time interval between disease onset and initiation of oral refeeding, total length of hospitalization (LOH), postrefeeding LOH, and adverse gastrointestinal events. RESULTS: There were 75 and 74 patients in the EORF group and the RORF group, respectively, with comparable baseline characteristics. Patients in the EORF group started refeeding significantly earlier than those in the RORF group (4.56 ± 1.53 vs 6.75 ± 2.29 days; P < 0.05). Moreover, patients in the EORF group had significantly shorter total (6.8 ± 2.1 vs 10.4 ± 4.1 days; P < 0.01) and post refeeding LOH (2.24 ± 0.52 vs 3.27 ± 0.61 days; P < 0.01). There was no significant difference in adverse gastrointestinal events between the 2 groups. CONCLUSION: In patients with mild AP, EORF, with the subjective feeling of hunger, is safe, feasible, and reduces LOH.

[The influnence of dachengqi tang on acute lung injury and intra abdominal hypertension in rats with acute pancreatitis].

OBJECTIVE: To test the hypothesis "lung and large intestine are interior exteriorly related" through investgating into the effect of Dacheng qi tang (DCQT) on intra abdominal hypertension (IAH) and acute lung injury (ALI) in rats with acute pancreatitis. METHODS: Male SD rats were randomly divided into three groups with ten rats for each group: rats with sham-operations (SO); rats with acute necrosis pancreatitis (ANP); rats with ANP plus DCQT treatment. ANP was induced by retrograde infusion of 5% taurocholic acid into pancreatic duct. Two hours after operations, 10 mL/kg of normal saline was orally adminstered to the rats in both SO and ANP groups, whereas 10 mL/kg DCQT was adminstered to the rats in the treatment group. Aterial blood, pancreas and lung tissues were collected for biomarkers and histopathology 24 hours after operations. Intra-abdominal pressure and intestinal propulsion rate were also measured. RESULTS; DCQT treatment reduced intra-abdominal pressure and improved intestinal propulsion rate compared with those treated with saline (P < 0.05). The ANP rats treated with DCQT had lower wet to dry weight ratio, and milder myeloperoxidase activity and histopathology changes in pancreas and lung than those treated with saline (P < 0.05). Higher pressure of oxygen (PO2) was found in the rats treated with DCQT, while no difference in PCO2 was found between the DCQT and ANP groups (P > 0.05). Only two rats in the ANP group died. CONCLUSION: DCQT can effectively relieve IAH and cure ALI at the same time in rats with acute pancreatitis. The result provides evidence to support the hypothesis "lung and large intestine are interior exteriorly related".

The cryoprotective effects of ascorbic acid supplementation on bovine semen quality.

To investigate the effects of ascorbic acid supplementation on standard semen quality parameters and antioxidant activities after thawing of bovine frozen semen, antioxidant ascorbic acid was added at concentrations of 2.5, 4.5, 6.5 and 8.5 mg/ml to bovine semen cryoprotective medium. The results showed that the sperm motility and motion characteristics were improved in the presence of ascorbic acid in extender, as compared to the control. The motility and straight linear velocity (VSL), linearity index (LIN), average path velocity (VAP), wobble coefficient (WOB), lateral head displacement (ALH) values and the percentage of "grade A" sperm in the extender supplemented with 4.5 mg/ml ascorbic acid were significantly higher than that of other treatment groups (P<0.05). The acrosome integrity and membrane integrity were significantly improved (P<0.05) by supplementing with 4.5 mg/ml ascorbic acid in the extender compared with a control. The extender supplemented with ascorbic acid did not lead to any improvement in superoxide dismutase (SOD) levels. The catalase (CAT) activity was higher in the extender supplemented with ascorbic acid at 4.5 mg/ml, when compared with other groups (P<0.05) and the extender supplemented with ascorbic acid significantly decreased glutathione peroxidase (GSH-Px) activity, whereas reduced glutathione (GSH) activities were significantly enhanced, compared with the control (P<0.05). Increasing the doses level of ascorbic acid decreased GSH-Px and GSH activity, the supplementation of 8.5 mg/ml ascorbic acid produced the lowest level of GSH-Px and GSH activity among groups (P<0.05). The extender supplemented with ascorbic acid could reduce the oxidative stress provoked by freezing-thawing and improve bovine semen quality. The particular properties of ascorbic acid are poorly related to its effectiveness in membrane cryopreservation. Further studies are required to determine lipid peroxidation and antioxidant capacities of ascorbic acid in cryopreserved bovine semen.