Moxibustion ameliorates ovarian function in premature ovarian insufficiency rats by activating cAMP/PKA/CREB to promote steroidogenesis in ovarian granulosa cells.

Premature ovarian insufficiency (POI) presents a substantial challenge to women's physiological and psychological well-being. Hormone replacement therapy, as the preferred therapeutic approach, involves solely exogenous supplementation of estrogen. Moxibustion, a traditional Chinese external treatment, has been investigated in our previous studies. It not only improves hormone levels and clinical symptoms in POI patients but also safeguards ovarian reserve. This study aims to explore the regulatory mechanisms by which moxibustion modulates hormone levels and restores ovarian function in POI. A POI rat model was established using cyclophosphamide, and moxibustion treatment was applied at acupoints "CV4" and "SP6" for a total of four courses. Subsequently, ovaries from each group were subjected to transcriptome sequencing (Bulk RNA-seq). Target pathways and key genes were selected through enrichment analysis and GSVA scoring, with validation using various techniques including electron microscopy, ELISA, Western blot, and immunohistochemistry. The results demonstrated that moxibustion restored the estrous cycle in POI rats, improved sex hormone levels, reduced the number of atretic follicles, and increased the count of dominant follicles (P<0.05). Bulk RNA-seq analysis revealed that moxibustion downregulated pathways associated with ovarian dysfunction, infertility, and immune responses, upregulated pathways related to follicular development and ovarian steroidogenesis. Furthermore, our data confirmed that moxibustion significantly increased the number of ovarian granulosa cells (GCs) and upregulated the expression of proteins related to steroidogenesis in GCs, including FSHR, P450 arom, cAMP, PKA, and CREB (P<0.05), with no significant effect observed on proteins related to steroidogenesis in theca cells. These outcomes aligned with the RNA-seq results. In conclusion, these findings propose that moxibustion enhances steroidogenesis in GCs through the activation of the cAMP/PKA/CREB pathway, consequently improving impaired ovarian function in POI rats. This study provides robust evidence supporting moxibustion as a targeted intervention for treating POI by specifically regulating steroidogenesis in GCs.

Efficacy and tolerability of sitagliptin and metformin compared with insulin as an initial therapy for newly diagnosed diabetic patients with severe hyperglycaemia.

The safety and efficacy of dipeptidyl peptidase-4 inhibitors in patients newly diagnosed type 2 diabetes mellitus (T2DM) with severe hyperglycaemia have remained to be sufficiently demonstrated. The aim of the present study was to determine whether sitagliptin combined with metformin as an initial treatment had non-inferior outcomes with regards to glycaemic remission and ß-cell function recovery to those of standard insulin therapy in this patient group. A prospective observational study was performed comparing the effects of sitagliptin combined with metformin and insulin therapy in a real-world clinical setting. A total of 168 participants were enrolled and received sitagliptin combined with metformin (Sig) or insulin (Ins) for almost 4 weeks. In addition, each group was further stratified into three subgroups, according to glycosylated haemoglobin (HbA1c) levels (<10, 10-12 and >12%). The primary outcomes were ß-cell function and changes in fasting plasma glucose (FPG) and HbA1c at the 3-month follow-up. Both insulin and sitagliptin combined with metformin reduced hyperglycaemia and achieved similar glycaemic outcomes, and no significant differences in FPG and HbA1c levels were obtained. No significant changes were observed in ß-cell function concomitant with the glucose-lowering effects of the treatments. Of note, participants in the Ins group exhibited weight gain, whereas those in the Sig group had weight loss, with significant differences becoming evident after 1 month, particularly in the HbA1c <10% subgroup. As compared with insulin injection, early treatment with sitagliptin combined with metformin in newly diagnosed patients with T2DM and severe hyperglycaemia produced non-inferior outcomes with regards to glycaemic remission. Therefore, combination of sitagliptin and metformin may be a viable initial treatment option for patients who prefer an alternative to insulin injection. This study was registered with ClinicalTrials.gov under no. NCT03180281.

Sphingosine-1-phosphate induces islet ß-cell proliferation and decreases cell apoptosis in high-fat diet/streptozotocin diabetic mice.

Sphingosine-1-phosphate (S1P) has been reported to enhance the function of islet ß-cells, providing a potential therapeutic target for diabetes mellitus. In the present study, the effects of S1P on the proliferation and apoptosis of ß-cells in type 2 diabetic mice were investigated. The mice were administered intraperitoneal S1P solution daily at a dose of 20 µg/kg for three weeks. The intraperitoneal glucose tolerance test (IPGTT) and homeostatic model assessment of insulin resistance (HOMA-IR) index determination were carried out. Immunohistochemical staining was used to detect the protein expression of insulin, antigen Ki-67 and S1P receptor isoforms (S1PR1/S1PR2/S1PR3) in pancreatic islets. Compared with the diabetic control (DC) group, the IPGTT results and HOMA-IR index in the S1P treatment group were decreased. The islets in the S1P group exhibited higher insulin immunostaining intensity than the DC group, as well as higher proliferation (P<0.05) and lower apoptosis rates (P<0.05). Positive staining for the S1P receptors S1PR1, S1PR2 and S1PR3 was observed in the cytoplasm and membrane of the islet cells. S1PR1 and S1PR2 proteins showed increased expression in the S1P and DC groups compared with the normal control group (P<0.01 and P<0.05, respectively), whereas no significant difference was observed in the expression of S1PR3 among these groups. In conclusion, extracellular S1P can induce islet ß-cell proliferation and decrease cell apoptosis in diabetic mice. S1P function may be mediated via S1PR1 and S1PR2; therefore, targeting S1P/S1PR signalling pathways may be a novel therapeutic strategy for diabetes mellitus.

Sphingolipid metabolism in type 2 diabetes and associated cardiovascular complications.

Sphingolipid metabolism is dysregulated in type 2 diabetes mellitus (T2DM); however, the focus of previous studies was mostly limited to ceramide (Cer), and only few studies have investigated other metabolites, including sphingosine-1 phosphate (So1P). The present study aimed to examine the involvement of 8 major sphingolipid metabolites, including Cer, glucosyl ceramide (GluCer), lactosyl ceramide (LacCer), sphingomyelin (SM), sphinganine (Sa), So1P, sphingosine (So) and sphinganine-1-phosphate (Sa1P), during the progression of T2DM, and to evaluate the ability of serum sphingolipids to predict cases of diabetes with an elevated risk of cardiovascular complications. Blood samples were obtained from 245 participants who were divided into 3 groups: Healthy controls, pre-diabetes (pre-DM) and diagnosed diabetes. The 8 major sphingolipid metabolites were measured by high-performance liquid chromatography-tandem mass spectrometry and blood parameters were determined by routine laboratory assays for all subjects. Among the sphingolipid metabolites, So1P was associated with sex and lean mass index, but not with the body mass index. So1P was highest in healthy controls and gradually decreased when the disease proceeded to pre-DM and T2DM. GluCer, SM, Sa and So decreased in pre-DM and rose again in T2DM, graphically exhibiting a 'U' shape change during the progression of diabetes. So1P and Sa were identified to be significantly associated with cardiovascular complications by multivariate logistic regression analysis. Receiver operating characteristic curve analysis also suggested that So1P and Sa were able to indicate cardiovascular complications in diabetic patients. Pre-DM and diabetes were significantly associated with decreased So1P, SM, Sa and So, compared with the healthy controls. So1P was correlated with the progression of T2DM, and was a predictor of an elevated risk of cardiovascular complications among T2DM patients, along with Sa. The present study was registered with ClinicalTrials.gov (no. NCT02826759; April 2016).