Anti-Hyperlipidemic Components of the Leaves of Synsepalum dulcificum (Miracle Fruit).

Synsepalum dulcificum (Miracle fruit) is a tropical plant in West and Central Africa, which has been historically used for treating diarrhea in humans and animals. Pharmacological research has shown that the leaves of the plant possess anti-hyperlipidemia activity. However, its anti-hyperlipidemic components have not been reported. In this study, the leaves of S. dulcificum were extracted using 95% ethanol and the extract was fractionated using different polar solvents. The anti-hyperlipidemia activity of the extract and fractions were evaluated using the zebrafish model. The results showed that the ethyl acetate (EA) fraction displayed the best anti-hyperlipidemic effect. A comparison of the high-performance liquid chromatography equipped with diode array detector (HPLC-DAD) profiles of the ethanol extract and different fractions at 350 nm indicated that a peak at 37.4 min has the highest intensity in the EA part, relatively. Then the chemical constituents of the extract and the active fraction were extensively identified using UPLC-Q-Exactive-Orbitrap-MS/MS, showing the main peak was quercitrin and other components in the EA part mainly included quercitrin analogs. Furthermore, the quercitrin was isolated from the plant and its contents in the extract and fractions were determined using high-performance liquid chromatography with ultraviolet detector (HPLC-UV) method. The quantitative results showed that the content of quercitrin in the EA fraction was 10.04% (w/w). Further pharmacological study indicated that quercitrin also possessed potent anti-hyperlipidemia activity (improvement rates of liver fat and total cholesterol were 75.6% and 92.5% at 40 µg/mL, respectively). Besides, quercitrin showed little toxicity to zebrafish embryos.

Recombinantly expressed rhFEB remodeled the skin defect of db/db mice.

Fibronectin (FN) and collagen are vital components of the extracellular matrix (ECM). These proteins are essential for tissue formation and cell alignment during the wound healing stage. In particular, FN interacts with collagens to activate various intracellular signaling pathways to maintain ECM stability. A novel recombinant extra domain-B fibronectin (EDB-FN)-COL3A1 fusion protein (rhFEB) was designed to mimic the ECM to promote chronic and refractory skin ulcer wound healing. rhFEB significantly enhanced cell adhesion and migration, vascular ring formation, and the production of new collagen I (COL1A1) in vitro. rhFEB decreased M1 macrophages and further modulated the wound microenvironment, which was confirmed by the treatment of db/db mice with rhFEB. Accelerated wound healing was shown during the initial stages in rhFEB-treated db/db mice, as was enhanced follicle regeneration, re-epithelialization, collagen deposition, granulation, inflammation, and angiogenesis. The wound chronicity of diabetic foot ulcers (DFUs) remains the main challenge in current and future treatment. rhFEB may be a candidate molecule for regulating M1 macrophages during DFU healing. KEY POINTS: • A recombinant protein EDB-FN-collagen III (rhFEB) was highly expressed in Escherichia coli • rhFEB protein induces COL1A1 secretion in human skin fibroblasts • rhFEB protein accelerates diabetic wound healing.

CUL3 induces mitochondrial dysfunction via MRPL12 ubiquitination in renal tubular epithelial cells.

Diabetic kidney disease (DKD) is the leading cause of chronic kidney disease worldwide and the strongest predictor of mortality in patients with diabetes. Despite its significance, the pathological mechanism underlying the onset and progression of DKD remains incompletely understood. In this study, we have shown that mitochondrial ribosomal protein L12 (MRPL12) plays a significant role in DKD by modulating mitochondrial function. We demonstrated that MRPL12 was mainly ubiquitinated at K150 in renal tubular epithelial cells. We have found that Cullin3 (CUL3), an E3 ubiquitin ligase, directly interacts with MRPL12 and induces the K63-linked ubiquitination of MRPL12, resulting in mitochondrial biosynthesis dysfunction. Moreover, under high-glucose (HG) conditions in renal tubular epithelial cells, we observed up-regulation of CUL3 expression, significant increase in CUL3-mediated ubiquitination of MRPL12 and dysregulation of mitochondrial biosynthesis. Notably, CUL3 knockdown stabilised the MRPL12 protein and protected mitochondrial biosynthesis under HG conditions. Our findings provide novel insight into how CUL3 affects mitochondrial biosynthesis in renal tubular epithelial cells through MRPL12 ubiquitination and suggest a potential therapeutic strategy for DKD in the future.

MRPL12-ANT3 interaction involves in acute kidney injury via regulating MPTP of tubular epithelial cells.

Acute kidney injury (AKI) is a serious disease with no effective treatment. Abnormal opening of mitochondrial permeability transition pore (MPTP) is an important pathological process in ischemia reperfusion injury (IRI), the key factor of AKI. It is essential to elucidate MPTP regulation mechanism. Here, we identified mitochondrial ribosomal protein L7/L12 (MRPL12) specifically binds to adenosine nucleotide translocase 3 (ANT3) under normal physiological conditions, stabilizes MPTP and maintains mitochondrial membrane homeostasis in renal tubular epithelial cells (TECs). During AKI, MRPL12 expression was significantly decreased in TECs, and MRPL12-ANT3 interaction was reduced, leading to ANT3 conformation change, MPTP abnormal opening, and cell apoptosis. Importantly, MRPL12 overexpression protected TECs from MPTP abnormal opening and apoptosis during hypoxia/reoxygenation (H/R). Our results suggest MRPL12-ANT3 axis involves in AKI by regulating MPTP, and MRPL12 could be potential intervention target for treatment of AKI.

Genome analysis of two Lactobacillus plantarum strains, LLY-606 and pc-26, for evaluating their potential as probiotics.

Lactobacillus plantarum was not only one of the most popular probiotics, but also one of the most versatile lactic acid bacteria. L. plantarum LLY-606 and L. plantarum pc-26 are strains isolated from human gut that are intended to be explored as probiotics. In this study, the genome sequences of LLY-606 and pc-26 were sequenced, and multiple genes related to probiotic properties were analyzed. First, the pathogenicity of these strains was evaluated, and antibiotic resistance genes were surveyed at the whole genome level to determine their primary safety. And then, genes for stress response, plantaricin (pln) biosynthesis, extracellular polysaccharide (EPS) biosynthesis, and bile salt hydrolase (BSH) were analyzed to evaluate their industrial utilization, adhesive capacity, and survival ability in gut, which were properties fundamental for probiotic strains. The physiological features assured by these genes were assayed in vitro. The strains were then evaluated in vivo for their ability to lower cholesterol, and they were both found to be effective in improving hypercholesterolemia in golden hamsters. In this study, a genetic pre-evaluation was conducted through genome analysis combined with in vitro physiological assay, and the probiotic properties of these strains were verified in vivo.