Uncovering a hidden functional role of the XRE-cupin protein PsdR as a novel quorum-sensing regulator in Pseudomonas aeruginosa.

XRE-cupin family proteins containing an DNA-binding domain and a cupin signal-sensing domain are widely distributed in bacteria. In Pseudomonas aeruginosa, XRE-cupin transcription factors have long been recognized as regulators exclusively controlling cellular metabolism pathways. However, their potential functional roles beyond metabolism regulation remain unknown. PsdR, a typical XRE-cupin transcriptional regulator, was previously characterized as a local repressor involved solely in dipeptide metabolism. Here, by measuring quorum-sensing (QS) activities and QS-controlled metabolites, we uncover that PsdR is a new QS regulator in P. aeruginosa. Our RNA-seq analysis showed that rather than a local regulator, PsdR controls a large regulon, including genes associated with both the QS circuit and non-QS pathways. To unveil the underlying mechanism of PsdR in modulating QS, we developed a comparative transcriptome approach named "transcriptome profile similarity analysis" (TPSA). Using this TPSA method, we revealed that PsdR expression causes a QS-null-like transcriptome profile, resulting in QS-inactive phenotypes. Based on the results of TPSA, we further demonstrate that PsdR directly binds to the promoter for the gene encoding the QS master transcription factor LasR, thereby negatively regulating its expression and influencing QS activation. Moreover, our results showed that PsdR functions as a negative virulence regulator, as inactivation of PsdR enhanced bacterial cytotoxicity on host cells. In conclusion, we report on a new QS regulation role for PsdR, providing insights into its role in manipulating QS-controlled virulence. Most importantly, our findings open the door for a further discovery of untapped functions for other XRE-Cupin family proteins.

Identification of antimicrobial-susceptible Pseudomonas aeruginosa RpoA variant strains through positional conservation pattern.

BACKGROUND: Bacterial RNA polymerase (RNAP) is a promising target for antimicrobial chemotherapy due to its indispensable role in bacterial growth and survival. Among its components, only the rpoB gene encoding the ß-subunit is known for its association with rifampicin resistance. We recently identified a variant of the RNAP α-subunit (RpoA) in Pseudomonas aeruginosa, conferring heightened bacterial susceptibility to antimicrobials. This susceptibility was attributed to the specific down-regulation of the MexEF-OprN efflux pump. OBJECTIVES: We asked how to distinguish antimicrobial-susceptible variant strains from clinical isolates. METHODS: In this study, we identified various P. aeruginosa RpoA variants from clinical sources. Using the sequence alignment of different bacterial RpoA species, we computed the positional conservation of substitutions in RpoA variants using Shannon Entropy. RESULTS: Our findings revealed that selective RpoA variant strains exhibited distinct profiles of antimicrobial susceptibility. Notably, RpoA variant strains, containing single-substitutions in the C-terminal domain (α-CTD) but not the N-terminal domain (α-NTD), showed attenuated MexEF-OprN expression and increased susceptibility to MexEF-OprN-specific antibiotics. Furthermore, we observed a close correlation between the susceptibility of these α-CTD RpoA variant strains to antibiotics and the conservation degrees of positional substitutions. CONCLUSIONS: Our findings demonstrate the prevalence of antimicrobial-susceptible RpoA variant strains among P. aeruginosa clinical isolates. The identified positional conservation pattern in our study facilitates the rapid classification of RpoA variant strains with distinct drug resistances. Given the high conservation of RNAP across bacterial species, our findings open a new therapeutic perspective for precisely and efficiently combating pathogenic RpoA variant strains with specific antimicrobials.

Diquat causes mouse testis injury through inducing heme oxygenase-1-mediated ferroptosis in spermatogonia.

Diquat dibromide (DQ) is a globally used herbicide in agriculture, and its overuse poses an important public health issue, including male reproductive toxicity in mammals. However, the effects and molecular mechanisms of DQ on testes are limited. In vivo experiments, mice were intraperitoneally injected with 8 or 10 mg/kg/ day of DQ for 28 days. It has been found that heme oxygenase-1 (HO-1) mediates DQ-induced ferroptosis in mouse spermatogonia, thereby damaging testicular development and spermatogenesis. Histopathologically, we found that DQ exposure caused seminiferous tubule disorders, reduced germ cells, and increased sperm malformation, in mice. Reactive oxygen species (ROS) staining of frozen section and transmission electron microscopy (TEM) displayed DQ promoted ROS generation and mitochondrial morphology alterations in mouse testes, suggesting that DQ treatment induced testicular oxidative stress. Subsequent RNA-sequencing further showed that DQ treatment might trigger ferroptosis pathway, attributed to disturbed glutathione metabolism and iron homeostasis in spermatogonia cells in vitro. Consistently, results of western blotting, measurements of MDA and ferrous iron, and ROS staining confirmed that DQ increased oxidative stress and lipid peroxidation, and accelerated ferrous iron accumulation both in vitro and in vivo. Moreover, inhibition of ferroptosis by deferoxamine (DFO) markedly ameliorated DQ-induced cell death and dysfunction. By RNA-sequencing, we found that the expression of HO-1 was significantly upregulated in DQ-treated spermatogonia, while ZnPP (a specific inhibitor of HO-1) blocked spermatogonia ferroptosis by balancing intracellular iron homeostasis. In mice, administration of the ferroptosis inhibitor ferrostatin-1 effectively restored the increase of HO-1 levels in the spermatogonia, prevented spermatogonia death, and alleviated the spermatogenesis disorders induced by DQ. Overall, these findings suggest that HO-1 mediates DQ-induced spermatogonia ferroptosis in mouse testes, and targeting HO-1 may be an effective protective strategy against male reproductive disorders induced by pesticides in agriculture.

The prevalence and risk factors of Trichomonas vaginalis in Wuhan and the Tibetan area, China: a two-center study.

Trichomonas vaginalis (T. vaginalis) infection is one of the most common sexually transmitted infections worldwide and is associated with several complications. However, the paucity of research regarding the prevalence of T. vaginalis infection in the Tibetan area limits control efforts. We aimed to evaluate the prevalence of T. vaginalis infection in the Tibetan area by a comparison with the prevalence of T. vaginalis in Wuhan city and to unveil the potential risk factors in the Tibetan area. This descriptive, cross-sectional study was conducted among adult women attending gynecology outpatient clinics in two public hospitals (one in Shannan city of Tibet and one in Wuhan city) in China in 2020. Data were retrieved from the medical record system and laboratory information management system, including T. vaginalis infection, bacterial vaginosis, and vulvovaginal candidiasis by wet mount microscopy or nucleic acid hybridization of vaginal secretions from patients. The associations of variables associated with T. vaginalis prevalence were quantified by odds ratios with 95% confidence intervals. The overall prevalence rates of T. vaginalis infection in the Tibetan area and Wuhan city were 20.94% and 2.84%, respectively. The statistically significant factors for the higher prevalence of T. vaginalis infection in the Tibetan area included tertiary educational status (AOR: 0.36 [95% CI: 0.16-0.81]), yearly family income > ¥100,000 (AOR: 0.48 [95% CI: 0.26-0.91]), clinical symptoms (AOR: 4.58[95% CI: 2.32-9.04]), and III-IV grade vaginal cleanliness (AOR: 29.71 [95% CI: 3.95-223.56]) in the multivariate logistic analysis. Interventions targeting improved living standards as well as women's educational level and promoting reproductive hygiene habits are recommended to contribute to the reduction in T. vaginalis infection in the Tibetan area.

Construction and evaluation of an antioxidant synergistic system containing vitamin C and vitamin E.

AIMS: The aim of this study is to develop a liposome that could exert unparalleled antioxidant effects. In the present study, a vitamin C (VC)/vitamin E (VE)-co-loaded multivesicular liposome (VCVE-MVL) was constructed. METHODS: Vitamins were encapsulated in soybean phosphatidylcholine (SPC) and cholesterol (CHO) by multi-emulsification method. The concentration of VC was determined by Fast Blue method. The concentration of VE was determined by high performance liquid chromatography (HPLC). Vitamin antioxidant capacity in vitro and in vivo was determined using ß-carotene bleaching. RESULTS: VCVE-MVL with particle diameter of 848.55 ± 0.29 nm and SPAN of 0.16 ± 0.11 were obtained. The encapsulation efficiency of VC reached 48.51% (w/w)±0.15. Compared with VC/VE solution, VCVE-MVL had a higher permeation efficiency. In addition, the in vitro and ex-vivo antioxidant tests verified the adequate antioxidant activity of VCVE-MVL. CONCLUSIONS: In conclusion, the antioxidant synergistic system we constructed and demonstrated its potential applications in the cosmetics industry.

T-17, a novel cyclin-dependent kinases/histone deacetylases dual inhibitor, induces cancer cells death through cell cycle arrest and apoptosis.

Combination of cyclin-dependent kinases (CDKs) and histone deacetylases (HDACs) inhibitors may have statistical synergy in suppressing cancer cell proliferation. Herein, a novel CDKs/HDACs dual inhibitor T-17 was rationally designed, synthesized, and evaluated. Our results demonstrated that T-17 concurrently exhibited potent and balanced inhibitory activity against CDKs (IC50 = 18.0 nM) and HDACs (IC50 = 6.6 nM) and also displayed good cell viability inhibitory effect on four cancer cell lines. Meanwhile, T-17 blocked the MDA-MB-231 and A549 cell cycle at G1 phase and S phase, respectively. In addition, T-17 induced MDA-MB-231 cells apoptosis and inhibited the HDACs and CDKs mediated signaling pathways. Finally, we also found that T-17 had good antitumor activity in vivo. In summary, these results indicated that T-17 would be a promising lead compound which deserves further research.

Interplay between Alzheimer's disease and global glucose metabolism revealed by the metabolic profile alterations of pancreatic tissue and serum in APP/PS1 transgenic mice.

Increasing evidence suggests that there is a correlation between type 2 diabetes mellitus (T2D) and Alzheimer's disease (AD). Increased Aß polypeptide production in AD patients would promote metabolic abnormalities, insulin signaling dysfunction and perturbations in glucose utilization, thus leading to the onset of T2D. However, the metabolic mechanisms underlying the interplay between AD and its diabetes-promoting effects are not fully elucidated. Particularly, systematic metabolomics analysis has not been performed for the pancreas tissues of AD subjects, which play key roles in the glucose metabolism of living systems. In the current study, we characterized the dynamic metabolic profile alterations of the serum and the pancreas of APP/PS1 double-transgenic mice (an AD mouse model) using the untargeted metabolomics approaches. Serum and pancreatic tissues of APP/PS1 transgenic mice and wild-type mice were extracted and subjected to NMR analysis to evaluate the functional state of pancreas in the progress of AD. Multivariate analysis of principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were conducted to define the global and the local (pancreas) metabolic features associated with the possible initiation of T2D in the progress of AD. Our results showed the onset of AD-induced global glucose metabolism disorders in AD mice. Hyperglycemia and its accompanying metabolic disorders including energy metabolism down-regulation and oxidative stress were observed in the serum of AD mice. Meanwhile, global disturbance of branched-chain amino acid (BCAA) metabolism was detected, and the change of BCAA (leucine) was positively correlated to the alteration of glucose. Moreover, increased level of glucose and enhanced energy metabolism were observed in the pancreas of AD mice. The results suggest that the diabetes-promoting effects accompanying the progress of AD are achieved by down-regulating the global utilization of glucose and interfering with the metabolic function of pancreas. Since T2D is a risk factor for the pathogenesis of AD, our findings suggest that targeting the glucose metabolism dysfunctions might serve as a supplementary therapeutic strategy for Alzheimer's disease.

The effects of phospholipase C on oestradiol and progesterone secretion in porcine granulosa cells cultured in vitro.

Granulosa cells play important roles in the regulation of ovarian functions. Phospholipase C is crucial in several signalling pathways and could participate in the molecular mechanisms of cell proliferation, differentiation and ageing. The objective of this study was to identify the effects of phospholipase C on the steroidogenesis of oestradiol and progesterone in porcine granulosa cells cultured in vitro. Inhibitor U73122 or activator m-3M3FBS of phospholipase C was added to the in vitro medium of porcine granulosa cells, respectively. The secretion of oestradiol decreased after 2 hr, 8 hr, 12 hr, 24 hr and 48 hr of treatment with 500 nM U73122 (p < .05) and decreased after 2 hr of treatment in the 500 nM m-3M3FBS addition group (p < .05). The secretion of progesterone increased after 4 hr of treatment with 500 nM U73122 (p < .05) and increased after 2 hr and 8 hr of treatment in the 500 nM m-3M3FBS addition group (p < .05). The ratio of oestradiol to progesterone decreased at each time point, except 8 hr after the addition of 500 nM U73122 (p < .05). The ratio of oestradiol to progesterone decreased after 2 hr (p < .05) of treatment with 500 nM m-3M3FBS. In genes that regulate the synthesis of oestradiol or progesterone, the mRNA expression of CYP11A1 was markedly increased (p < .05), and the mRNA expression of other genes did not change significantly in the U73122 treatment group, while the addition of m-3M3FBS did not change those genes significantly despite the contrary trend. Our results demonstrated that phospholipase C can be a potential target to stimulate the secretion of oestradiol and suppress progesterone secretion in porcine granulosa cells cultured in vitro, which shed light on a novel biological function of phospholipase C in porcine granulosa cells.

Raf-ERK1/2 signalling pathways mediate steroid hormone synthesis in bovine ovarian granulosa cells.

Steroid hormones are required for normal reproductive function of female. The aim of this study was to investigate the role of Raf-ERK1/2 on steroid hormone synthesis in bovine ovarian granulosa cells. Immunohistochemistry assay showed that both B-Raf and C-Raf were expressed in granulosa cells, theca cells and Sertoli cells. The protein expression of Raf or ERK1/2 was clearly decreased by Raf inhibitor GSK2118436 or ERK1/2 inhibitor SCH772984, respectively (p < 0.05). In addition, western blotting was performed for investigating the crosstalk between Raf and ERK1/2, the data showed that Raf positively regulated ERK1/2, whereas ERK1/2 had a negative feedback effect on Raf. The biosynthesis of oestradiol or testosterone was significantly decreased by treatment with GSK2118436 or SCH772984 (p < 0.05). Conversely, the progesterone biosynthesis was clearly increased by treatment with those inhibitors (p < 0.05). Furthermore, the mRNA expression of STAR, aromatase and CYP17 was blocked by Raf-ERK1/2 signalling inhibition, which oppositely induced the mRNA expression of CYP11. Together, these findings suggested that Raf-ERK1/2 signalling pathways mediate steroid hormone synthesis via affecting the expression of steroidogenic enzymes.

SIRT2 Inhibition Results in Meiotic Arrest, Mitochondrial Dysfunction, and Disturbance of Redox Homeostasis during Bovine Oocyte Maturation.

SIRT2, a member of the sirtuin family, has been recently shown to exert important effects on mitosis and/or metabolism. However, its roles in oocyte maturation have not been fully clarified. In this study, SIRT2, located in the cytoplasm and nucleus, was found in abundance in the meiotic stage, and its expression gradually decreased until the blastocyst stage. Treatment with SIRT2 inhibitors resulted in the prevention of oocyte maturation and the formation of poor-quality oocytes. By performing confocal scanning and quantitative analysis, the results showed that SIRT2 inhibition induced prominent defects in spindle/chromosome morphology, and led to the hyperacetylation of α-tubulin and H4K16. In particular, SIRT2 inhibition impeded cytoplasmic maturation by disturbing the normal distribution of cortical granules, endoplasmic reticulum, and mitochondria during oocyte meiosis. Meanwhile, exposure to SirReal2 led to elevated intracellular reactive oxygen species (ROS) accumulation, low ATP production, and reduced mitochondrial membrane potential in oocytes. Further analysis revealed that SIRT2 inhibition modulated mitochondrial biogenesis and dynamics via the downregulation of TFAM and Mfn2, and the upregulation of DRP1. Mechanistically, SIRT2 inhibition blocked the nuclear translocation of FoxO3a by increasing FoxO3a acetylation, thereby downregulating the expression of FoxO3a-dependent antioxidant genes SOD2 and Cat. These results provide insights into the potential mechanisms by which SIRT2-dependent deacetylation activity exerts its effects on oocyte quality.

Sequential delivery of VEGF, FGF-2 and PDGF from the polymeric system enhance HUVECs angiogenesis in vitro and CAM angiogenesis.

Angiogenesis is an organized series of events, beginning with vessel destabilization, followed by endothelial cell re-organization, and ending with vessel maturation. The formation of a mature vascular network requires precise spatial and temporal regulation of a large number of angiogenic factors, including vascular endothelial growth factor (VEGF), basic fibroblast growth factor-2 (FGF-2) and platelet-derived growth factor (PDGF). VEGF aids in vascular permeability and endothelial cell recruitment, FGF-2 activates endothelial cell proliferation and migration while PDGF stimulates vascular stability. Accordingly, VEGF may inhibit vessel stabilization while PDGF may inhibit endothelial cell recruitment. Therefore, a new polymeric system was prepared by the supercritical carbon dioxide foaming technology, which realized sequential delivery of two or more growth factors with the controlled dose and rate. Increased release of VEGF (71.10%) and FGF-2 (69.76%) compared to PDGF (43.17%) was observed for the first 7 days. Thereafter, up till 21 days, an increased rate of release of BMP-2 compared to VEGF 165 was observed. The effects of PDGF-PLAms/VEGF-FGF-2-PLGA scaffolds on angiogenesis were investigated by human umbilical vein endothelial cells (HUVECs) angiogenic differentiation in vitro and chorioallantoic membrane (CAM) angiogenesis in vivo. Sequential delivery of VEGF, FGF-2 and PDGF from structural polymer scaffolds with distinct kinetics resulted in significant angiogenic differentiation of HUVECs and rapid formation of mature vascular networks in chorioallantoic membrane. This study reported a composite scaffold with distinct release kinetics, and these results clearly indicated the importance of sequential delivery of multiple growth factors in tissue regeneration and engineering.

SIRT6 protects cardiomyocytes against ischemia/reperfusion injury by augmenting FoxO3α-dependent antioxidant defense mechanisms.

SIRT6, a member of the NAD(+)-dependent class III deacetylase sirtuin family, has been revealed to play important roles in promoting cellular resistance against oxidative stress. The formation of reactive oxygen species (ROS) and oxidative stress are the crucial mechanisms underlying cellular damage and dysfunction in cardiac ischemia/reperfusion (I/R) injury, but the role of SIRT6 in I/R-induced ROS and oxidative stress is poorly understood. In this study, by using heterozygous SIRT6 knockout (SIRT6(+/-)) mice and cultured neonatal cardiomyocyte models, we investigated how SIRT6 mediates oxidative stress and myocardial injury during I/R. Partial knockout (KO) of SIRT6 aggravated myocardial damage, ventricular remodeling, and oxidative stress in mice subjected to myocardial I/R, whereas restoration of SIRT6 expression by direct cardiac injection of adenoviral constructs encoding SIRT6 reversed these deleterious effects of SIRT6 KO in the ischemic heart. In addition, partial deletion of the SIRT6 gene decreased myocardial functional recovery following I/R in a Langendorff perfusion model. Similarly, the protective effects of SIRT6 were also observed in cultured cardiomyocytes following hypoxia/reoxygenation. Intriguingly, SIRT6 was noticed to up-regulate AMP/ATP and then activate the adenosine 5'-monophosphate-activated protein kinase (AMPK)-forkhead box O3α (FoxO3α) axis and further initiated the downstream antioxidant-encoding gene expression (manganese superoxide dismutase and catalase), thereby decreasing cellular levels of oxidative stress and mediating cardioprotection in the ischemic heart. These results suggest that SIRT6 protects the heart from I/R injury through FoxO3α activation in the ischemic heart in an AMP/ATP-induced AMPK-dependent way, thus upregulating antioxidants and suppressing oxidative stress.

Effects of melatonin on follicular atresia and granulosa cell apoptosis in the porcine.

The accumulation of reactive oxygen species is detrimental to the health of the ovarian follicle. The protective, antioxidant properties of melatonin, an endogenous component of porcine follicular fluid, on apoptosis of granulosa cells were evaluated in this study. Porcine granulosa cells from medium-sized (3-5 mm), healthy follicles were cultured in serum-free conditions with melatonin (0, 0.01, 0.1, 1.0, 10, and 100 ng/mL) with or without its receptor antagonist, luzindole, followed by evaluation of apoptotic markers in the treated cells. Results revealed that endogenous, intrafollicular melatonin concentration decreased as follicular atresia progressed, whereas the percentage of apoptotic granulosa cells increased. Spontaneous apoptosis of granulosa cells, triggered by serum deprivation in vitro, was remarkably blocked by melatonin (1.0 ng/mL melatonin, 32.7 ± 0.5%, vs. control, 47.0 ± 1.0%; P < 0.05). Treatment with 1.0 ng/mL of melatonin also significantly elevated MT2, SOD1, and GPX4 while lowering FASL, CHOP, and GRP78 mRNA abundance compared to the untreated control. The anti-apoptotic effect and some changes of apoptotic-relevant genes in granulosa cells invoked by melatonin supplementation were markedly blocked by luzindole, suggesting that melatonin could prevent the apoptosis of porcine granulosa cells during follicular atresia via its membrane receptors and its free-radical-scavenging activity. These findings provide new insights into the regulatory mechanism of melatonin in follicular atresia-related functions. Mol. Reprod. Dev. 83: 692-700, 2016 © 2016 Wiley Periodicals, Inc.

Chromatographic elution process design space development for the purification of saponins in Panax notoginseng extract using a probability-based approach.

A Monte Carlo method was used to develop the design space of a chromatographic elution process for the purification of saponins in Panax notoginseng extract. During this process, saponin recovery ratios, saponin purity, and elution productivity are determined as process critical quality attributes, and ethanol concentration, elution rate, and elution volume are identified as critical process parameters. Quadratic equations between process critical quality attributes and critical process parameters were established using response surface methodology. Then probability-based design space was computed by calculating the prediction errors using Monte Carlo simulations. The influences of calculation parameters on computation results were investigated. The optimized calculation condition was as follows: calculation step length of 0.02, simulation times of 10 000, and a significance level value of 0.15 for adding or removing terms in a stepwise regression. Recommended normal operation region is located in ethanol concentration of 65.0-70.0%, elution rate of 1.7-2.0 bed volumes (BV)/h and elution volume of 3.0-3.6 BV. Verification experiments were carried out and the experimental values were in a good agreement with the predicted values. The application of present method is promising to develop a probability-based design space for other botanical drug manufacturing process.

Process development for the decoloration of Panax notoginseng extracts: a design space approach.

A systematic, yet simple method for the decoloration of Panax notoginseng extracts has been developed by static adsorption tests and response surface methodology. Through static adsorption experiment screening, acidic alumina was selected because of its high decoloration ratio and saponin recovery ratios. Using response surface methodology, the correlation between the process parameters (i.e., sample volume and flow rate) and decoloration performance was modeled. A design space of the decoloration process was subsequently established through the proposed models. The verification experimental values were in good agreement with the predicted values. The design space was proven reliable, because all the verification experimental results attained the criteria for design space development. Moreover, most of the saponins adsorbed by the acidic alumina could be recovered through dynamic desorption using water and ethanol. The method developed in the current study is highly efficient, flexible, and easy to control, thus providing a promising approach for the decoloration of Panax notoginseng extracts with consistent decoloration performance.

Performance of field demonstration nanoscale zero-valent iron in groundwater remediation: A review.

Nanoscale zero-valent iron (nZVI) has gained widespread usage in groundwater remediation due to its exceptional reactivity. Since its initial deployment in field demonstrations in 2001, nZVI has proven to be an effective nanomaterial for addressing groundwater contaminants. Subsequent research has highlighted the versatility of nZVI, showcasing its potential to overcome critical limitations associated with conventional remediation technologies. The effectiveness of nZVI in remediation varies, contingent on factors such as the type of nZVI, contaminant nature, site conditions, and injection methodologies employed. This review aims to present a comprehensive progress report on the field application of nZVI spanning 22 years across eight countries. Drawing from a database encompassing 32 pilot or full-scale remediation sites, the study delineates the various types of nZVI, modification methods, demonstration sites, and primary contaminants targeted in field tests. Specific attention is given to the application effects and mechanisms of unmodified nZVI, Pd, surfactants, and carbon-modified nZVI in diverse field demonstrations. An analysis of the key factors influencing their performance is provided, and potential future applications of nZVI in groundwater remediation are discussed.

Polypeptides as alternatives to PEGylation of therapeutic agents.

INTRODUCTION: Due to the concerns raised by the extensive application of PEGylation, polypeptides have stood out as excellent candidates with adequate biocompatibility and biodegradability with tunable hydrophilicity. AREAS COVERED: In this review, polypeptides with the potential to replace PEGylation have been summarized and their application has been reviewed, including XTEN, PASylation, polysarcosine, zwitterion polypeptides, ELPylation, etc. Besides their strengths, the remaining challenges have also been discussed and the future perspectives have been provided. EXPERT OPINION: Polypeptides have been applied in the designing of peptide/protein drugs as well as nanomedicines, and some of the pharmaceutics have made it into the clinical trials and got approved. These polypeptides showed similar hydrophilic properties to PEGylation, which increased the hydrodynamic volumes of protein drugs, reduced kidney elimination, decreased protein-polymer interaction and potentially improved the drug delivery efficiency due to the extended circulation time in the system. Moreover, they demonstrated superior biodegradability and biocompatibility, compensating for the deficiencies for polymers such as PEG.

Sulforaphane reduces adipose tissue fibrosis via promoting M2 macrophages polarization in HFD fed-mice.

Adipose tissue fibrosis has been identified as a novel contributor to the pathomechanism of obesity associated metabolic disorders. Sulforaphane (SFN) has been shown to have an anti-obesity effect. However, the impact of SFN on adipose tissue fibrosis is still not well understood. In this study, obese mice induced by high-fat diets (HFD) were used to examine the effects of SFN on adipose tissue fibrosis. According to the current findings, SFN dramatically enhanced glucose tolerance and decreased body weight in diet-induced-obesity (DIO) mice. Additionally, SFN therapy significantly reduced extracellular matrix (ECM) deposition and altered the expression of genes related to fibrosis. Furthermore, SFN also reduced inflammation and promoted macrophages polarization towards to M2 phenotype in adipose tissue, which protected adipose tissue from fibrosis. Notably, SFN-mediated nuclear factor E2-related factor 2 (Nrf2) activation was crucial in decreasing adipose tissue fibrosis. These results implied that SFN had favorable benefits in adipose tissue fibrosis, which consequently ameliorates obesity-related metabolic problems. Our research provides new treatment strategies for obesity and associated metabolic disorders.

Preparation of etoposide liposomes for enhancing antitumor efficacy on small cell lung cancer and reducing hematotoxicity of drugs.

Etoposide (VP16) is commonly used in the treatment of small cell lung cancer (SCLC) in clinical practice. However, severe adverse reactions such as bone marrow suppression toxicity limit its clinical application. Although several studies on VP16 liposomes were reported, no significant improvement in bone marrow suppression toxicity has been found, and there was a lack of validation of animal models for in vivo antitumor effects. Therefore, we attempted to develop a PEGylated liposomal formulation that effectively encapsulated VP16 (VP16-LPs) and evaluated its therapeutic effect and toxicity at the cellular level and in animal models. First, we optimized the preparation process of VP16-LPs using an orthogonal experimental design and further prepared them into freeze-dried powder to improve storage stability of the product. Results showed that VP16-LPs freeze-dried powder exhibited good dispersibility and stability after redispersion. In addition, compared to marketed VP16 injection, VP16-LPs exhibited sustained drug release characteristics. At the cellular level, VP16-LPs enhanced the cellular uptake of drugs and exhibited strong cytotoxic activity. In animal models, VP16-LPs could target and aggregate in tumors and exhibit a higher anti-tumor effect than VP16-injection after intravenous injection. Most importantly, hematological analysis results showed that VP16-LPs significantly alleviated the bone marrow suppression toxicity of drug. In summary, our study confirmed that PEGylated liposomes could enhance therapeutic efficacy and reduce toxicity of VP16, which demonstrated that VP16-LPs had enormous clinical application potential.

Isorhamnetin Improves Oocyte Maturation by Activating the Pi3k/Akt Signaling Pathway.

SCOPE: Isorhamnetin is a natural flavonoid with various pharmacological activities, which can be widely and continuously ingested by humans and animals through their daily diet. The aim of this study is to explore the benefits and molecular mechanisms of isorhamnetin on oocyte maturation. METHODS AND RESULTS: Oocytes are incubated with isorhamnetin (5, 10, 20, and 30 µM) for 44 h. Isorhamnetin (10 µM) increases the polar body extrusion rate of oocytes. Furthermore, isorhamnetin alleviates oxidative stress by inhibiting reactive oxygen species levels and stimulating SOD2 protein expression. The changes in intracellular mitochondrial autophagy and apoptosis-related proteins (Bcl-2, Bax/Bcl-2, and C-Casp3) indicate that isorhamnetin inhibits oocyte apoptosis. Isorhamnetin inhibits endoplasmic reticulum stress by reducing the protein expression of CHOP and GRP78 and improving the normal distribution rate of endoplasmic reticulum. Mechanistic studies show that isorhamnetin activates the PI3K/Akt signaling pathway. CONCLUSION: Isorhamnetin promotes oocyte maturation by inhibiting oxidative stress, mitochondrial dysregulation, apoptosis, and endoplasmic reticulum stress, which have important potential for improving oocyte quality and treating female infertility.