Enhancing ß-cell function and identity in type 2 diabetes: The protective role of Coptis deltoidea C. Y. Cheng et Hsiao via glucose metabolism modulation and AMPK signaling activation.

BACKGROUND: Abnormalities in glucose metabolism may be the underlying cause of ß-cell dysfunction and identity impairment resulting from high glucose exposure. In China, Coptis deltoidea C. Y. Cheng et Hsiao (YL) has demonstrated remarkable hypoglycemic effects. HYPOTHESIS/PURPOSE: To investigate the hypoglycemic effect of YL and determine the mechanism of YL in treating diabetes. METHODS: A type 2 diabetes mouse model was used to investigate the pharmacodynamics of YL. YL was administrated once daily for 8 weeks. The hypoglycemic effect of YL was assessed by fasting blood glucose, an oral glucose tolerance test, insulin levels, and other indexes. The underlying mechanism of YL was examined by targeting glucose metabolomics, western blotting, and qRT-PCR. Subsequently, the binding capacity between predicted AMP-activated protein kinase (AMPK) and important components of YL (Cop, Ber, and Epi) were validated by molecular docking and surface plasmon resonance. Then, in AMPK knockdown MIN6 cells, the mechanisms of Cop, Ber, and Epi were inversely confirmed through evaluations encompassing glucose-stimulated insulin secretion, markers indicative of ß-cell identity, and the examination of glycolytic genes and products. RESULTS: YL (0.9 g/kg) treatment exerted notable hypoglycemic effects and protected the structural integrity and identity of pancreatic ß-cells. Metabolomic analysis revealed that YL inhibited the hyperactivated glycolysis pathway in diabetic mice, thereby regulating the products of the tricarboxylic acid cycle. KEGG enrichment revealed the intimate relationship of this process with the AMPK signaling pathway. Cop, Ber, and Epi in YL displayed high binding affinities for AMPK protein. These compounds played a pivotal role in preserving the identity of pancreatic ß-cells and amplifying insulin secretion. The mechanism underlying this process involved inhibition of glucose uptake, lowering intracellular lactate levels, and elevating acetyl coenzyme A and ATP levels through AMPK signaling. The use of a glycolytic inhibitor corroborated that attenuation of glycolysis restored ß-cell identity and function. CONCLUSION: YL demonstrates significant hypoglycemic efficacy. We elucidated the potential mechanisms underlying the protective effects of YL and its active constituents on ß-cell function and identity by observing glucose metabolism processes in pancreatic tissue and cells. In this intricate process, AMPK plays a pivotal regulatory role.

Full-length transcriptome analysis of Coptis deltoidea and identification of putative genes involved in benzylisoquinoline alkaloids biosynthesis based on combined sequencing platforms.

KEY MESSAGE: The study carry out comprehensive transcriptome analysis of C. deltoidea and exploration of BIAs biosynthesis and accumulation based on UHPLC-MS/MS and combined sequencing platforms. Coptis deltoidea is an important medicinal plant with a long history of medicinal use, which is rich in benzylisoquinoline alkaloids (BIAs). In this study, Ultra performance liquid chromatography-electrospray ionization tandem mass spectrometry (UHPLC-ESI-MS/MS) and combined sequencing platforms were performed for exploration of BIAs biosynthesis, accumulation and comprehensive transcriptome analysis of C. deltoidea. By metabolism profiling, the accumulation of ten BIAs was analyzed using UHPLC-MS/MS and different contents were observed in different organs. From transcriptome sequencing result, we applied single-molecule real-time (SMRT) sequencing to C. deltoidea and generated a total of 75,438 full-length transcripts. We proposed the candidate biosynthetic pathway of tyrosine, precursor of BIAs, and identified 64 full length-transcripts encoding enzymes putatively involved in BIAs biosynthesis. RNA-Seq data indicated that the majority of genes exhibited relatively high expression level in roots. Transport of BIAs was also important for their accumulation. Here, 9 ABC transporters and 2 MATE transporters highly homologous to known alkaloid transporters related with BIAs transport in roots and rhizomes were identified. These findings based on the combined sequencing platforms provide valuable genetic information for C. deltoidea and the results of transcriptome combined with metabolome analysis can help us better understand BIAs biosynthesis and transport in this medicinal plant. The information will be critical for further characterization of C. deltoidea transcriptome and molecular-assisted breeding for this medicinal plant with scarce resources.

Ultrahigh-performance liquid chromatography with tandem mass spectrometry for the determination of 10 alkaloids in beagle plasma after the oral administration of the three Coptidis rhizoma extracts.

ETHNOPHARMACOLOGICAL RELEVANCE: Coptidis rhizoma (CR) is the dried rhizome of the ranunculaceous plant CR. For decades in China, this plant has been used to treat hypertension, hyperlipidemia, and chronic diarrhea and has been officially included in the Chinese Pharmacopoeia. The present paper presents a review of the pharmacokinetics of CR. AIM OF THE STUDY: The pharmacokinetic studies and differences of 10 alkaloids among Coptis deltoidea C. Y. cheng et Hsiao, Coptis chinensis Franch and Coptis teeta Wall. Are seldom reported. This study is the first to determine corydaline, dehydrocorydaline, tetrahydropalmatine, palmatine, magnoflorine, jatrorrhizine, berberine, worenine, berberrubine, and coptisine, which adopted an ultrahigh-performance liquid chromatography-electrospray ionization-tandem mass spectrometry, simultaneously. MATERIALS AND METHODS: Chromatographic separation was performed within 8 min by using an Agilent SB-C18 column (150 mm × 2.1 mm, 1.8 µm) with gradient mobile phase consisting of 0.3% acetic acid water (v/v) and acetonitrile at a flow rate of 0.3 mL/min. Multiple reaction monitoring mode was used to detect the tandem mass spectrum in the positive ionization mode by electrospray ionization source. RESULTS: The method was fully validated to be linear over a wide concentration (r > 0.9916), and the linear concentration range was 0.195-2260 ng/mL. Intra- and interday precisions were below 14.19% and 18.56% for the 10 analytes, respectively. The accuracy ranged from -9.30% to 6.31%. The extraction recovery of the 10 alkaloids and internal standard ranged from 79.76% to 95.37%. Pharmacokinetic comparative study showed that the Cmax and AUC0-∞ values of dehydrocorydaline, tetrahydropalmatine, palmatine, magnoflorine, jatrorrhizine, berberine, worenine, berberrubine, and coptisine increased significantly (p < 0.05), which was different for beagles after oral administration. The results can help determine the mechanism of action and guide clinical application of these three extracts. CONCLUSION: This validated method was successfully applied for the pharmacokinetics study of beagle plasma after oral administration of three CR extract types.

Difference of hypoglycemic and hypolipidemic effects of endangered species (Coptis deltoidea) and its processed products on T2DM rats / 中草药

Objective To investigate the difference of hypoglycemic and hypolipidemic effects of Coptis deltoidea (Coptis chinensis) and its processed products on T2DM rats. Methods Type 2 diabetes mellitus induced by high sugar, high fat diet and low dose of streptozotocin. C. deltoidea were processed with yellow wine, ginger, and evodia rutaecarpa, respectively. The effects of C. deltoidea on fasting blood glucose (FBG), fasting insulin (FINS), glycosylated serum protein (GSP), pancreatic pathology, serum triglyceride (TG), total cholesterol (TC) and lipoprotein (HDL-C or LDL-C) and key protein and gene expression of SCAP\SREBP-1c pathway in liver of model rats were investigated. Result C. deltoidea and its processed products reduced the FBG and GSP in T2DM rats. The wine products significantly reduced FBG and GSP in model rats (P < 0.01). The hypoglycemic range was better than raw and ginger products. At hypolipidemic aspect, C. deltoidea and its processed products decreased the content of TG, TC, and LDL-C (P < 0.05, 0.01), increased the content of HDL-C in serum (P < 0.05, 0.01), and down-regulated the protein and gene expression of SCAP/SREBP-1c in liver, the insulin target organ. However, wine and evodia products were better than crude drug or ginger products. Conclusion C. deltoidea processed by yellow wine, ginger and evodia rutaecarpa is traditional method to improve the disadvantages of C. deltoidea with bitter cold nature and not easy to take for a long time. However, different processing methods have different effects. Clinical medication should be combied withTCM syndrome differentiation and simple hypoglycemic effect of wine product is appropriate; while wine and evodia products were better in hypoglycemic and lipid regulation aspects.

[Hypolipidemic effect of Coptis chinensis and C. deltoidea on type 2 diabetes rats through SCAP/SREBP-1c signal pathway].

The type 2 diabetes rat model was induced with high-sugar and high-fat diet combined with low-dose STZ. This study investigated the hypolipidemic mechanism of Coptis chinensis and C. deltoidea. After 30 days of administration, HOMA-IR and the content of TG in serum were detected, and the expressions of SCAP, SREBP-1c were tested by the method of Western blot and Real-time PCR analysis. The test results showed that both components can significantly alleviate insulin resistance and down-regulate the expressions of SREBP-1c and SCAP in liver tissue of type two diabetes mellitus. Compared with the control group, there were significant differences in relevant protein expression (P<0.05, P<0.01). This indicates that the inhibition of SREBP-1c and SCAP expressions may be the hypolipidemic mechanism of Coptidis Rhizoma on type 2 diabetes mellitus. The results also showed that C. deltoidea has a better efficacy in lipid elimination, but a weaker hypoglycemic effect against C. chinensis.

Hypolipidemic effect of Coptis chinensis and C. deltoidea on type 2 diabetes rats through SCAP/SREBP-1c signal pathway / 中国中药杂志

The type 2 diabetes rat model was induced with high-sugar and high-fat diet combined with low-dose STZ. This study investigated the hypolipidemic mechanism of Coptis chinensis and C. deltoidea. After 30 days of administration, HOMA-IR and the content of TG in serum were detected, and the expressions of SCAP, SREBP-1c were tested by the method of Western blot and Real-time PCR analysis. The test results showed that both components can significantly alleviate insulin resistance and down-regulate the expressions of SREBP-1c and SCAP in liver tissue of type two diabetes mellitus. Compared with the control group, there were significant differences in relevant protein expression (<0.05, <0.01). This indicates that the inhibition of SREBP-1c and SCAP expressions may be the hypolipidemic mechanism of Coptidis Rhizoma on type 2 diabetes mellitus. The results also showed that C. deltoidea has a better efficacy in lipid elimination, but a weaker hypoglycemic effect against C. chinensis.