Oral nano-formulation improves pancreatic islets dysfunction via lymphatic transport for antidiabetic treatment

Type 2 diabetes mellitus (T2DM) therapy is facing the challenges of long-term medication and gradual destruction of pancreatic islet β-cells. Therefore, it is timely to develop oral prolonged action formulations to improve compliance, while restoring β-cells survival and function. Herein, we designed a simple nanoparticle with enhanced oral absorption and pancreas accumulation property, which combined apical sodium-dependent bile acid transporter-mediated intestinal uptake and lymphatic transportation. In this system, taurocholic acid (TCA) modified poly(lactic-co-glycolic acid) (PLGA) was employed to achieve pancreas location, hydroxychloroquine (HCQ) was loaded to execute therapeutic efficacy, and 1,2-dilauroyl-sn-glycero-3-phosphocholine (DLPC) was introduced as stabilizer together with synergist (PLGA-TCA/DLPC/HCQ). In vitro and in vivo results have proven that PLGA-TCA/DLPC/HCQ reversed the pancreatic islets damage and dysfunction, thus impeding hyperglycemia progression and restoring systemic glucose homeostasis via only once administration every day. In terms of mechanism PLGA-TCA/DLPC/HCQ ameliorated oxidative stress, remodeled the inflammatory pancreas microenvironment, and activated PI3K/AKT signaling pathway without obvious toxicity. This strategy not only provides an oral delivery platform for increasing absorption and pancreas targetability but also opens a new avenue for thorough T2DM treatment.

Mechanism of taurocholic acid in promoting the progression of liver cirrhosis / 临床肝胆病杂志

Bile acid is the main component of bile, and the external secretion of bile acid into the intestine can help with the absorption of lipids and fat-soluble vitamins; in addition, bile acid acts as a signal molecule to regulate bile acid metabolism and help maintain intestinal homeostasis. The process of liver cirrhosis is accompanied by varying degrees of cholestasis, causing bile duct injury, and exposure of liver cells to a high concentration of bile acid will accelerate the progression of liver cirrhosis and form a vicious circle. Among these abnormally elevated bile acids, taurocholic acid (TCA) shows the greatest increase, suggesting that TCA may play an important role in the process of liver cirrhosis. At present, there are relatively few studies on the mechanism of TCA in liver cirrhosis, and current studies in China and globally have shown that TCA at a high concentration (≥50 μmol/L) can promote the progression of liver cirrhosis by acting on liver cells (hepatic stellate cells, hepatocytes, hepatic progenitor cells, and bile duct epithelial cells). This article discusses the detailed mechanism of TCA in promoting liver cirrhosis and points out that TCA has the clinical potential as a biomarker and therapeutic target for liver cirrhosis.

Simultaneous quantification of chlorogenic acid and taurocholic acid in human plasma by LC-MS/MS and its application to a pharmacokinetic study after oral administration of Shuanghua Baihe tablets / 中国天然药物

An LC-MS/MS method was developed and validated for the simultaneous quantification of chlorogenic acid (CGA) and taurocholic acid (TCA) in human plasma using hydrochlorothiazide as the internal standard. The chromatographic separation was achieved on a Hedera ODS-2 column with a gradient elution using 10 mmol·L(-1) of ammonium acetate buffer solution containing 0.5% of formic acid - acetonitrile as mobile phase at a flow rate of 300 μL·min(-1). The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring in negative ESI mode. The method was fully validated over the concentration ranges of 0.1-10 ng·mL(-1) for CGA and 2-150 ng·mL(-1) for TCA. It was successfully applied to a pharmacokinetic study of CGA and TCA in healthy Chinese volunteers after oral administration of Shuanghua Baihe tablets (SBTs). In the single-dose study, the maximum plasma concentration (Cmax), time to reach Cmax (Tmax) and elimination half-life (t1/2) of CGA were (0.763 8 ± 0.542 0) ng·mL(-1), (1.0 ± 0.5) h, and (1.3 ± 0.6) h, respectively. In the multiple-dose study, the Cmax, Tmax and t1/2 of CGA were (0.663 7 ± 0.583 3) ng·mL(-1), (1.1 ± 0.5) h, and (1.4 ± 0.7) h, respectively. For TCA, no significant characteristic increasing plasma TCA concentration-time curve was found in the volunteers after oral administration of SBTs, indicating its complicated process in vivo as an endogenous ingredient.

Establishment and identification of HEK293 cell lines with stable and high expression of NTCP / 中国药理学通报

Abstrate:Aim To construct HEK293 cell line with stable and high expression of sodium taurocholate cotransporting polypeptide (NTCP ) efficiently and rapidly.Method Vector expressing EGFP-NTCP fusion protein was constructed and verified by DNA sequencing.The pEGFP-NTCP expression vector was transfected into HEK293 cells by FuGENE 6 transfection reagent. The transfected cells with high expression of green fluorescent protein were selected using fluorescence microscope for screening of G418 for 14 days to obtain cell lines stably and highly expressing NTCP.NTCP expression was detected by RT-PCR,qRT-PCR, Western-blot and the uptake experiment of taurocholic acid.Re-sult RT-PCR,qRT-PCR,Western-blot and the uptake experi-ment revealed that compared to the control cells,the expression of NTCP was significantly positive (P<0.01)in stable trans-fected cells showing green fluorescence (P<0.05 ).Conclusion The HEK293 cell line with stable and high expression of NTCP has been established efficiently and rapidly,which provides a cellular model for the study of the mechanism of the uptake of bile acid derivatives.

N-Acetylcysteine Improves Pancreatic Microcirculation and Alleviates the Severity of Acute Necrotizing Pancreatitis

BACKGROUND/AIMS: To investigate the beneficial effect of N-Acetylcysteine (NAC) on pancreatic microvascular perfusion in acute necrotizing pancreatitis (ANP). METHODS: Fifty-four rats were divided into a control group, an ANP group and an NAC-treated group. The ANP model was established by a retrograde injection of 3% sodium taurocholate into the pancreatic duct. The NAC-treated group received an intravenous infusion of NAC just 2 hours before and 30 minutes after the induction of ANP. The pancreatic microvascular perfusion was measured with laser Doppler flowmetry and pancreatic samples were collected for histological examination. RESULTS: The microvascular perfusion in the NAC-treated group decreased slightly and exhibited a significant increase compared to the ANP group (p<0.01). A pathological examination revealed that edema and inflammatory infiltration decreased, and the hemorrhaging and necrosis of the pancreas were significantly reduced. CONCLUSIONS: NAC could improve pancreatic microvascular perfusion and alleviate the severity of sodium taurocholate-induced ANP, possibly representing a new therapeutic approach to prevent the progression of ANP.

Effects of Intravenous Administration of Taurocholate on Liver and Serum Thiosulfate Sulfurtransferase Activities in Cholestatic Rat

PURPOSE: To Study the possible mechanisms of change of thiosulfate sulfurtransferase (TST) activity in cholestatic rat liver and serum. METHODS: Rats were divided into seven groups: those receiving a sham operation (Sham group), with a bile duct obstruction (BDO) alone (BDO group), with a BDO plus taurocholic acid (TCA) injection (BDO plus TCA group), with a BDO plus tauroursodeoxycholic acid (TUDCA) injection (BDO plus TUDCA group), a choledocho-caval shunt (CCS) operation (CCS groups), a CCS operation plus TCA injection (CCS plus TCA group) and a CCS operation plus TUDCA injection (CCS plus TUDCA group). The TST activities in the serum and in the hepatic subcellular fractions isolated from above experimental rats were determined. The Km and Vmax values of this hepatic enzyme were measured. RESULTS: The liver cytosolic, mitochondrial and microsomal TSTs activities, as well as the TST Vmax values were found to be significantly decreased in the BDO plus TCA and BDO groups compared to the control group. The activity and Vmax value of the liver cytosolic TST were also found to be significantly decreased in the CCS plus TCA group. Conversely, there was no variation in the Km values of the hepatic enzymes in any of the above experimental groups. The serum TST activities in the CCS plus TCA and BDO plus TCA groups, were significantly increased compared with the control, CCS and BDO groups. However, the serum and hepatic enzyme activities were unchanged in both the CCS plus TUDCA and BDO plus TUDCA groups. CONCLUSION: The above results indicate that TCA represses the biosynthesis of TST in the liver. Also, the elevated TST activity in the serum is most likely due to an increase in the permeability of hepatocytes membrane upon TCA mediated liver cell necrosis.

Effects of Intravenous Administration of Taurocholate on Liver and Serum Thiosulfate Sulfurtransferase Activities in Cholestatic Rat

PURPOSE: To Study the possible mechanisms of change of thiosulfate sulfurtransferase (TST) activity in cholestatic rat liver and serum. METHODS: Rats were divided into seven groups: those receiving a sham operation (Sham group), with a bile duct obstruction (BDO) alone (BDO group), with a BDO plus taurocholic acid (TCA) injection (BDO plus TCA group), with a BDO plus tauroursodeoxycholic acid (TUDCA) injection (BDO plus TUDCA group), a choledocho-caval shunt (CCS) operation (CCS groups), a CCS operation plus TCA injection (CCS plus TCA group) and a CCS operation plus TUDCA injection (CCS plus TUDCA group). The TST activities in the serum and in the hepatic subcellular fractions isolated from above experimental rats were determined. The Km and Vmax values of this hepatic enzyme were measured. RESULTS: The liver cytosolic, mitochondrial and microsomal TSTs activities, as well as the TST Vmax values were found to be significantly decreased in the BDO plus TCA and BDO groups compared to the control group. The activity and Vmax value of the liver cytosolic TST were also found to be significantly decreased in the CCS plus TCA group. Conversely, there was no variation in the Km values of the hepatic enzymes in any of the above experimental groups. The serum TST activities in the CCS plus TCA and BDO plus TCA groups, were significantly increased compared with the control, CCS and BDO groups. However, the serum and hepatic enzyme activities were unchanged in both the CCS plus TUDCA and BDO plus TUDCA groups. CONCLUSION: The above results indicate that TCA represses the biosynthesis of TST in the liver. Also, the elevated TST activity in the serum is most likely due to an increase in the permeability of hepatocytes membrane upon TCA mediated liver cell necrosis.

Effects of Intravenous Administration of Taurocholate on Hepatic Thiol Methyltransferase Activity in Cholestatic Rat

PURPOSE: The possible mechanisms of increased thiol me thyltransferase (TMT) activity in cholestatic rat livers and serum were studied. METHODS: Rats were divided into seven groups: rats receiv ing a sham operation, rats with a bile duct obstruction (BDO) alone (BDO group), rats with BDO plus taurocholic acid (TCA) injection (BDO plus TCA group), rats with BDO plus tauroursodeoxycholic acid (TUDCA) injection (BDO plus TUDCA group), rats receiving a choledoco-caval shunt (CCS) operation (CCS groups), rats receiving a CCS operation plus TCA Injection (CCS plus TCA group), and rats receiving a CCS operation plus TUDCA injection (CCS plus TUDCA group). The TMT activities in the serum and in the hepatic subcellular fractions isolated from these experimental rats were determined. The values of Km and Vmax in this he patic enzyme were measured. RESULTS: The activities of liver mitochondrial and microsomal TMTs as well as the Vmax values of TMT were found to be increased significantly in both the CCS plus TCA and the BDO plus TCA groups, compared with the CCS and BDO groups. On the other hand, the Km values of hepatic subcellular TMT were the same in all experimental groups. The serum TMT activity increased significantly in both the CCS plus TCA and the BDO plus TCA groups, compared with the control, CCS and BDO groups. However, these serum and hepatic enzyme activities were the same in the CCS plus TUDCA and the BDO plus TUDCA groups. CONCLUSION: The above results suggest that TCA stimulates the biosynthesis of TMT in the liver. Also, the elevated TMT activity in the serum is thought to be caused by an increase in membrane permeability of hepatocytes from liver cell necrosis caused by TCA.

Induction of Rat Liver gamma-Glutamyl Transpeptidase by Bile Acid Load / 대한간학회지

BACKGROUND/AIMS: In order to elucidate the possible mechanism of increase of y-glutamyl transpeptidase (y-GTP) activity in cholestatic liver and serum was studied. METHOD: Rats were divided into eight groups: Normal, sham operated control, bile duct obstruction (BDO) alone (BDO group), BDO plus taurocholic acid (TCA) injection (BDO plus TCA group), BDO plus tauroursodeoxycholic acid (TUDCA) injection (BDO plus TUDCA group), choledoco-caval shunt (CCS) operation (CCS groups), CCS plus TCA injection (CCS plus TCA group), and CCS plus TUDCA injection (CCS plus TUDCA group). Y-GTP activity was determined in the serum and liver cytosolic, mitochondrial and microsomal preparations isolated from above experimental rats. The values of Km and Vmax in this hepatic enzyme was measured. RESULT: the activities of liver cytosolic and microsomal y-GTP showed a significant increase in the CCS group. The activities of liver cytosolic, mitochondrial and microsomal y-GTP showed a significant increase in the BDO group. And the activity of serum y-GTP showed a marked increase in teth CCS and BDO poups. However, y-GTP activities in the serum and in liver microsomal prepatation rose more rapidly in the BDO group tban CCS. Y-GTP activity in liver cytosolic and microsomal preparatians, and its Vmax value incmmxl significantly in both CCS plus TCA group, and BDO plus TCA group than each control group, such as CCS and BDO group. On the other hand, the values of Km of the hepatic subcellular y-GTP did not change in the all experimental groups. Sennn y-GTP activity increased significantly in both CCS plus 7CA group, and BDO plus TCA group than each control group. However, these serum and hepatic enzyme activities did not change in both CCS plus TUDCA group and BDO plus TUDCA group. CONCLUSIONS: The above results suggest that 7CA stimulates biosynthesis of the y-GTP in the liver. And the elevations of the serum enzymes activity thought to be caused by increase of hepatocyte membrane permeability by a physical property (detergency) of TCA, which cause the enzyme to leak into the blood in large quantities.

Determination of taurocholic acid in Shedanchuanbei Oral Liquid and snake bile by SPE-HPLC / 中成药

Objective: To establish the method for determination of taurocholic acid in the Traditional Chinese Medicine Shedanchuanbei Oral Liquid and snake bile. Methods: The sample was prepared as mixed solution containing methanol and KH 2PO 4. The mixed solution was injected into Sep Pak C 18 cartridge for the purpose of sample purity. In this processing, the substances which having strong retain action and could harm analytic column were hold in the Sep Pak C 18 cartridge. The eluting solution that the Sep Pak C 18 cartridge had be over loading for taurocholic acid was used as the test solution. The test solution was measured by RP HPLC. The chromatographic conditions were as followed: Supelcosil LC 8 column(150mm?4.6nm,5?m) as analytic column, detect wavelength at 203nm, and MeOH 0.4%KH 2PO 4 mixed solution(56∶44, V/V ) as mobile phase. The inject volume was 50?L. Results: The linear response range of sodium taurocholate was from 0.0253mg?mL -1 to 0.253mg?mL -1 , and the correlation coefficient was 0.9999. The average recovery rate was 101.3%, RSD was 0.40%( n =6). Conclusion: This method was simple, efficient and suitable to the quality control for Shedanchuanbei Oral Liquid and snake bile.