Investigation of the MDM2-binding potential of de novo designed peptides using enhanced sampling simulations.

The tumor suppressor p53 plays a crucial role in cellular responses to various stresses, regulating key processes such as apoptosis, senescence, and DNA repair. Dysfunctional p53, prevalent in approximately 50 % of human cancers, contributes to tumor development and resistance to treatment. This study employed deep learning-based protein design and structure prediction methods to identify novel high-affinity peptide binders (Pep1 and Pep2) targeting MDM2, with the aim of disrupting its interaction with p53. Extensive all-atom molecular dynamics simulations highlighted the stability of the designed peptide in complex with the target, supported by several structural analyses, including RMSD, RMSF, Rg, SASA, PCA, and free energy landscapes. Using the steered molecular dynamics and umbrella sampling simulations, we elucidate the dissociation dynamics of p53, Pep1, and Pep2 from MDM2. Notable differences in interaction profiles were observed, emphasizing the distinct dissociation patterns of each peptide. In conclusion, the results of our umbrella sampling simulations suggest Pep1 as a higher-affinity MDM2 binder compared to p53 and Pep2, positioning it as a potential inhibitor of the MDM2-p53 interaction. Using state-of-the-art protein design tools and advanced MD simulations, this study provides a comprehensive framework for rational in silico design of peptide binders with therapeutic implications in disrupting MDM2-p53 interactions for anticancer interventions.

SMC-5/6 complex subunit NSE-1 plays a crucial role in meiosis and DNA repair in Caenorhabditis elegans.

The SMC5/6 complex is evolutionarily conserved across all eukaryotes and plays a pivotal role in preserving genomic stability. Mutations in genes encoding SMC5/6 complex subunits have been associated with human lung disease, immunodeficiency, and chromosome breakage syndrome. Despite its critical importance, much about the SMC5/6 complex remains to be elucidated. Various evidences have suggested possible role of a subunit of the SMC5/6 complex, NSE1, in chromosome segregation and DNA repair. Current knowledge regarding the role of NSE1 is primarily derived from single-cell-based analyses in yeasts, Arabidopsis thaliana, and human cell lines. However, our understanding of its function is still limited and requires further investigation. This study delves into the role of nse-1 in Caenorhabditis elegans, revealing its involvement in meiotic recombination and DNA repair. nse-1 mutants display reduced fertility, increased male incidence, and increased sensitivity to genotoxic chemicals due to defects in meiotic chromosome segregation and DNA repair. These defects manifest as increased accumulation of RAD-51 foci, increased chromosome fragmentation, and susceptibility to MMS, cisplatin, and HU. Furthermore, nse-1 mutation exacerbates germ cell death by upregulating ced-13 and egl-1 genes involved in the CEP-1/p53-mediated apoptotic pathway. NSE-1 is essential for the proper localization of NSE-4 and MAGE-1 on the chromosomes. Collectively, these findings firmly establish nse-1 as a crucial factor in maintaining genomic stability.

Dual tagging of GFP and Degron on endogenous COSA-1 in Caenorhabditis elegans as a crossover investigation tool.

COSA-1 is essential for accurate meiosis in C. elegans . Two null mutants ( cosa-1 ( me13 ) and cosa-1 ( tm3298 ) ) have been notably studied. These null mutants exhibit severe meiotic defects, hindering the observation of the subtle or dynamic nature of COSA-1 function. To overcome these limitations, we developed a C. elegans strain with inducible COSA-1 degradation using the Auxin-Inducible Degron (AID) system. This strain exhibits normal fertility and COSA-1::GFP foci. Auxin treatment successfully depletes COSA-1, resulting in a 96% decrease in progeny viability and 12 univalent chromosomes in diakinesis oocytes. This strain serves as a valuable tool for studying the dynamics of COSA-1.

Ganoderma lucidum methyl ganoderate E extends lifespan and modulates aging-related indicators in Caenorhabditis elegans.

Methyl Ganoderate E (MGE) is a triterpenoid derived from Ganoderma lucidum (Reishi), an edible mushroom, commonly processed into food forms such as soups, drinks, culinary dishes, and supplements. MGE has been shown to inhibit 3T3-L1 murine adipocyte differentiation when combined with other G. lucidum triterpenes. However, the specific effect of MGE on biological processes remains unknown. In this study, we present the first evidence of MGE's anti-aging effect in Caenorhabditis elegans. Through our screening process using the UPRER regulation ability, we evaluated a library of 74 pure compounds isolated from G. lucidum, and MGE exhibited the most promising results. Subsequent experiments demonstrated that MGE extended the lifespan by 26% at 10 µg ml-1 through daf-16, hsf-1, and skn-1-dependent pathways. MGE also enhanced resistance to various molecular stressors, improved healthspan, increased fertility, and reduced the aggregation of alpha-synuclein and amyloid-beta. Transcriptome data revealed that MGE promoted processes associated with proteolysis and neural activity, while not promoting cell death processes. Collectively, our findings suggest that G. lucidum MGE could be considered as a potential anti-aging intervention, adding to the growing list of such interventions.

Disparate roles for C. elegans DNA translocase paralogs RAD-54.L and RAD-54.B in meiotic prophase germ cells.

RAD54 family DNA translocases partner with RAD51 recombinases to ensure stable genome inheritance, exhibiting biochemical activities both in promoting recombinase removal and in stabilizing recombinase association with DNA. Understanding how such disparate activities of RAD54 paralogs align with their biological roles is an ongoing challenge. Here we investigate the in vivo functions of Caenorhabditis elegans RAD54 paralogs RAD-54.L and RAD-54.B during meiotic prophase, revealing distinct contributions to the dynamics of RAD-51 association with DNA and to the progression of meiotic double-strand break repair (DSBR). While RAD-54.L is essential for RAD-51 removal from meiotic DSBR sites to enable recombination progression, RAD-54.B is largely dispensable for meiotic DSBR. However, RAD-54.B is required to prevent hyperaccumulation of RAD-51 on unbroken DNA during the meiotic sub-stage when DSBs and early recombination intermediates form. Moreover, DSB-independent hyperaccumulation of RAD-51 foci in the absence of RAD-54.B is RAD-54.L-dependent, revealing a hidden activity of RAD-54.L in promoting promiscuous RAD-51 association that is antagonized by RAD-54.B. We propose a model wherein a division of labor among RAD-54 paralogs allows germ cells to ramp up their capacity for efficient homologous recombination that is crucial to successful meiosis while counteracting potentially deleterious effects of unproductive RAD-51 association with unbroken DNA.

Caenorhabditis elegans NSE3 homolog (MAGE-1) is involved in genome stability and acts in inter-sister recombination during meiosis.

Melanoma antigen (MAGE) genes encode for a family of proteins that share a common MAGE homology domain. These genes are conserved in eukaryotes and have been linked to a variety of cellular and developmental processes including ubiquitination and oncogenesis in cancer. Current knowledge on the MAGE family of proteins mainly comes from the analysis of yeast and human cell lines, and their functions have not been reported at an organismal level in animals. Caenorhabditis elegans only encodes 1 known MAGE gene member, mage-1 (NSE3 in yeast), forming part of the SMC-5/6 complex. Here, we characterize the role of mage-1/nse-3 in mitosis and meiosis in C. elegans. mage-1/nse-3 has a role in inter-sister recombination repair during meiotic recombination and for preserving chromosomal integrity upon treatment with a variety of DNA-damaging agents. MAGE-1 directly interacts with NSE-1 and NSE-4. In contrast to smc-5, smc-6, and nse-4 mutants which cause the loss of NSE-1 nuclear localization and strong cytoplasmic accumulation, mage-1/nse-3 mutants have a reduced level of NSE-1::GFP, remnant NSE-1::GFP being partially nuclear but largely cytoplasmic. Our data suggest that MAGE-1 is essential for NSE-1 stability and the proper functioning of the SMC-5/6 complex.

Isolation, Identification and Molecular Mechanism Analysis of the Nematicidal Compound Spectinabilin from Newly Isolated Streptomyces sp. DT10.

Plant parasitic nematodes (PPNs) are highly destructive and difficult to control, while conventional chemical nematicides are highly toxic and cause serious environmental pollution. Additionally, resistance to existing pesticides is becoming increasingly common. Biological control is the most promising method for the controlling of PPNs. Therefore, the screening of nematicidal microbial resources and the identification of natural products are of great significance and urgency for the environmentally friendly control of PPNs. In this study, the DT10 strain was isolated from wild moss samples and identified as Streptomyces sp. by morphological and molecular analysis. Using Caenorhabditis elegans as a model, the extract of DT10 was screened for nematicidal activity, which elicited 100% lethality. The active compound was isolated from the extracts of strain DT10 using silica gel column chromatography and semipreparative high-performance liquid chromatography (HPLC). The compound was identified as spectinabilin (chemical formula C28H31O6N) using liquid chromatography mass spectrometry (LC-MS) and nuclear magnetic resonance (NMR). Spectinabilin exhibited a good nematicidal activity on C. elegans L1 worms, with a half-maximal inhibitory concentration (IC50) of 2.948 µg/mL at 24 h. The locomotive ability of C. elegans L4 worms was significantly reduced when treated with 40 µg/mL spectinabilin. Further analysis of spectinabilin against known nematicidal drug target genes in C. elegans showed that it acts via target(s) different from those of some currently used nematicidal drugs such as avermectin and phosphine thiazole. This is the first report on the nematicidal activity of spectinabilin on C. elegans and the southern root-knot nematode Meloidogyne incognita. These findings may pave the way for further research and application of spectinabilin as a potential biological nematicide.

Polysaccharides Extracted from Dendrobium officinale Grown in Different Environments Elicit Varying Health Benefits in Caenorhabditis elegans.

Dendrobium officinale is one of the most widely used medicinal herbs, especially in Asia. In recent times, the polysaccharide content of D. officinale has garnered attention due to the numerous reports of its medicinal properties, such as anticancer, antioxidant, anti-diabetic, hepatoprotective, neuroprotective, and anti-aging activities. However, few reports of its anti-aging potential are available. Due to high demand, the wild D. officinale is scarce; hence, alternative cultivation methods are being employed. In this study, we used the Caenorhabditis elegans model to investigate the anti-aging potential of polysaccharides extracted from D. officinale (DOP) grown in three different environments; tree (TR), greenhouse (GH), and rock (RK). Our findings showed that at 1000 µg/mL, GH-DOP optimally extended the mean lifespan by 14% and the maximum lifespan by 25% (p < 0.0001). TR-DOP and RK-DOP did not extend their lifespan at any of the concentrations tested. We further showed that 2000 µg/mL TR-DOP, GH-DOP, or RK-DOP all enhanced resistance to H2O2-induced stress (p > 0.05, p < 0.01, and p < 0.01, respectively). In contrast, only RK-DOP exhibited resistance (p < 0.01) to thermal stress. Overall, DOP from the three sources all increased HSP-4::GFP levels, indicating a boost in the ability of the worms to respond to ER-related stress. Similarly, DOP from all three sources decreased α-synuclein aggregation; however, only GH-DOP delayed ß-amyloid-induced paralysis (p < 0.0001). Our findings provide useful information on the health benefits of DOP and also provide clues on the best practices for cultivating D. officinale for maximum medicinal applications.

MasitinibL shows promise as a drug-like analog of masitinib that elicits comparable SARS-Cov-2 3CLpro inhibition with low kinase preference.

SARS-CoV-2 infection has led to several million deaths worldwide and ravaged the economies of many countries. Hence, developing therapeutics against SARS-CoV-2 remains a core priority in the fight against COVID-19. Most of the drugs that have received emergency use authorization for treating SARS-CoV-2 infection exhibit a number of limitations, including side effects and questionable efficacy. This challenge is further compounded by reinfection after vaccination and the high likelihood of mutations, as well as the emergence of viral escape mutants that render SARS-CoV-2 spike glycoprotein-targeting vaccines ineffective. Employing de novo drug synthesis or repurposing to discover broad-spectrum antivirals that target highly conserved pathways within the viral machinery is a focus of current research. In a recent drug repurposing study, masitinib, a clinically safe drug against the human coronavirus OC43 (HCoV-OC43), was identified as an antiviral agent with effective inhibitory activity against the SARS-CoV-2 3CLpro. Masitinib is currently under clinical trial in combination with isoquercetin in hospitalized patients (NCT04622865). Nevertheless, masitinib has kinase-related side effects; hence, the development of masitinib analogs with lower anti-tyrosine kinase activity becomes necessary. In this study, in an attempt to address this limitation, we executed a comprehensive virtual workflow in silico to discover drug-like compounds matching selected pharmacophore features in the SARS-CoV-2 3CLpro-bound state of masitinib. We identified a novel lead compound, "masitinibL", a drug-like analog of masitinib that demonstrated strong inhibitory properties against the SARS-CoV-2 3CLpro. In addition, masitinibL further displayed low selectivity for tyrosine kinases, which strongly suggests that masitinibL is a highly promising therapeutic that is preferable to masitinib.

Modulation of immunological responses by aqueous extract of Datura stramonium L. seeds on cyclophosphamide-induced immunosuppression in Wistar rats.

BACKGROUND: Datura stramonium L. (Solanaceae) is used traditionally in west Africa to treat asthma, epilepsy, rheumatoid arthritis, filariasis microbial infections and conjunctivitis. This study investigated the immunomodulatory effects of aqueous seed extract of D. stramonium L. (ASEDS) on Wistar rats. METHODS: Thirty Wistar albino rats (180-200 g) were randomized into 6 groups (n = 5). Group 1 received distilled water only. Rats in groups 2-6 were pretreated with 10 mg/kg body weight (b.w.) Cyclophosphamide orally for 27-days to induce immunosuppression. Thereafter, they received treatment orally for 28 days as follows: Group 2 (distilled water), group 3 (5 mg/kg b.w. Levamisole), groups 4-6 (60, 90 and 120 mg/kg b.w. ASEDS, respectively). HPLC was used to determine major compounds in ASEDS. The effects of ASEDS on immune cells, immunoglobulins A, G and M levels, lipoproteins, and antioxidant status of rats were evaluated. RESULTS: ASEDS indicated high content of Acutumine, Quinine, Catechin, Chlorogenic acid, Gallic acid, Quercetin, Vanillic acid, Luteolin, Formosanin C, Saponin, Cyanidin, Tannic acid, 3-Carene, Limonene and α-terpineol. Cyclophosphamide triggered significant (p < 0.05) reduction in total leucocyte count and differentials, IgA, IgG, high-density lipoproteins (HDL), catalase, superoxide dismutase, glutathione peroxidase, vitamins A, C and E levels of untreated rats. Administration of ASEDS led to significant (p < 0.05) improvement in immune cell counts, immunoglobulin synthesis, high-density lipoprotein concentration, and antioxidant status of rats in the treated groups. CONCLUSIONS: The results obtained from the study showed the immunomodulatory activity of ASEDS, thereby indicating its potential in immunostimulatory drug discovery.

An endogenous mCherry-tagged COSA-1 as a crossover investigation tool in Caenorhabditis elegans.

The C. elegans cosa-1 gene encodes the crossover site-associated-1 (COSA-1) protein, a cyclin-related protein that functions in promoting crossovers (COs) during meiosis. Previous studies regarding CO dynamics in live C. elegans have mostly relied on the green fluorescent protein-tagged cosa-1 transgenic strain, which was generated by the microparticle bombardment method. Here, we insert the red fluorescence protein mCherry at the C-terminal of the cosa-1 gene to establish cosa-1::mCherry transgenic worm by the CRISPR/Cas9 technique. The COSA-1::mCherry was observed to appear from the early pachytene, and disappear in the diplotene zone of the germline, with 6 COSA-1:: mCherry foci in the late pachytene, which colocalized with GFP::COSA-1 from AV630 strain. Furthermore, the transgenic strain harboring a cosa-1::mCherry fusion shows no defect in the brood size, progeny viability and male frequency, which provides a useful tool for the meiotic analysis in C. elegans .

Phosphomannose Isomerase Is Involved in Development, Stress Responses, and Pathogenicity of Aspergillus flavus.

Aspergillus flavus causes invasive aspergillosis in immunocompromised patients and severe contamination of agriculturally important crops by producing aflatoxins. The fungal cell wall is absent in animals and is structurally different from that of plants, which makes it a potential antifungal drug target due to its essentiality for fungal survival. Mannose is one of the important components in the fungal cell wall, which requires GDP-mannose (GDP-Man) as the primary donor. Three consecutive enzymes, namely, phosphomannose isomerase (PMI), phosphomannose mutase (PMM), and GDP-mannose phosphorylase (GMPP), are required for GDP-Man biosynthesis. Thus, PMI is of prime importance in cell wall biosynthesis and also has an active role in sugar metabolism. Here, we investigated the functional role of PMI in A. flavus by generating a pmiA-deficient strain. The mutant required exogenous mannose to survive and exhibited reduced growth rate, impaired conidiation, early germination, disturbance in stress responses, and defects in colonization of crop seeds. Furthermore, attenuated virulence of the mutant was documented in both Caenorhabditis elegans and Galleria mellonella infection models. Our results suggested that PMI plays an important role in the development, stress responses, and pathogenicity of A. flavus and therefore could serve as a potential target for battling against infection and controlling aflatoxin contamination caused by A. flavus. IMPORTANCE Aspergillus flavus is a common fungal pathogen of humans, animals, and agriculturally important crops. It causes invasive aspergillosis in humans and also produces highly carcinogenic mycotoxins in postharvest crops that threaten food safety worldwide. To alleviate or eliminate the threats posed by A. flavus, it is necessary to identify genes involved in pathogenicity and mycotoxin contamination. However, little progress has been made in this regard. Here, we focused on PMI, which is the first enzyme involved in the biosynthesis pathway of GDP-Man and thus is important for cell wall synthesis and protein glycosylation. Our study revealed that PMI is important for growth of A. flavus. It is also involved in conidiation, germination, morphogenesis, stress responses, and pathogenicity of A. flavus. Thus, PMI is a potent antifungal target to curb the threats posed by A. flavus.

Loss of NSE-4 Perturbs Genome Stability and DNA Repair in Caenorhabditis elegans.

The Structural Maintenance of Chromosomes (SMC) complex plays an important role in maintaining chromosome integrity, in which the SMC5/6 complex occupies a central position by facilitating mitotic and meiotic processes as well as DNA repair. NSE-4 Kleisin is critical for both the organization and function of the SMC5/6 complex, bridging NSE1 and NSE3 (MAGE related) with the head domains of the SMC5 and SMC6 proteins. Despite the conservation in protein sequence, no functional relevance of the NSE-4 homologous protein (NSE-4) in Caenorhabditis elegans has been reported. Here, we demonstrated the essential role of C. elegans NSE-4 in genome maintenance and DNA repair. Our results showed that NSE-4 is essential for the maintenance of chromosomal structure and repair of a range of chemically induced DNA damage. Furthermore, NSE-4 is involved in inter-sister repair during meiosis. NSE-4 localizes on the chromosome and is indispensable for the localization of NSE-1. Collectively, our data from this study provide further insight into the evolutionary conservation and diversification of NSE-4 function in the SMC-5/6 complex.

A New Variant of Mutational and Polymorphic Signatures in the ERG11 Gene of Fluconazole-Resistant Candida albicans.

Background: Resistance to antifungal drugs for treating Candida infections remains a major concern globally despite the range of medications available. Most of these drugs target key proteins essential to the life cycle of the organism. An enzyme essential for fungal cell membrane integrity, lanosterol 14-α demethylase (CYP51), is encoded by the ERG11 gene in Candida species. This enzyme is the target of azole-based drugs. The organism has, however, devised molecular adaptations to evade the activity of these drugs. Materials and Methods: Classical methods were employed to characterize clinical isolates sampled from women and dogs of reproductive age. For fluconazole efficacy studies, CLSI guidelines on drug susceptibility testing were used. To understand the susceptibility pattern, various molecular and structural analytic approaches, including sequencing, in silico site-directed mutagenesis, and protein-ligand profiling, were applied to the ERG11 gene and CYP51 protein sequences. Several platforms, comprising Clustal Omega, Pymol plugin manager, Pymol molecular visualizer, Chimera-curated Dynameomics rotamer library, protein-ligand interaction profiler, Charmm36 force field, GROMACS, Geneious, and Mega7, were employed for this analysis. Results: The following Candida species distribution was obtained: 37.84% C. albicans, 8.12% C. glabrata, 10.81% C. krusei, 5.41% C. tropicalis, and 37.84% of other unidentified Candida species. Two codons in the nucleotide sequence of the wild-type (CTC and CCA) coding for LEU-370 and PRO-375, respectively, were mutated to L370S and P375H in the resistant strain. The mutation stabilized the protein at the expense of the heme moiety. We found that the susceptible isolate from dogs (Can-iso-029/dog) is closely related to the most resistant isolate from humans. Conclusion: Taken together, our results showed new mutations in the heme-binding pocket of caCYP51 that explain the resistance to fluconazole exhibited by the Candida isolates. So far, the L370S and P375H resistance-linked mutations have not been previously reported.

Ethyl acetate fraction of Fagara zanthoxyloides root-bark possess antidiabetic property against alloxan-induced diabetes and its complications in Wistar rat model.

ETHNOPHARMACOLOGICAL RELEVANCE: Fagara zanthoxyloides Lam., an African traditional medicinal plant, is used for treatment of malaria and diabetes. AIM: To investigate the antidiabetic property of ethyl acetate fraction of F. zanthoxyloides root-bark (EAFFZRB) on alloxan-induced diabetic rats. MATERIALS AND METHODS: Extraction, isolation, preliminary phytochemical analysis, and acute toxicity study of ethanol extract and fractions of F. zanthoxyloides root-bark were achieved using standard methods. Phyto-constituents in EAFFZRB were identified using HPLC technique. Forty-eight male Wistar rats (140-185 g) were randomized into 6 groups (n = 8). Groups 1 and 2 served as normal and negative controls, respectively. Diabetes was induced in test groups (2-6) using 150 mg/kg body weight (b.w) Alloxan monohydrate. Rats in groups 4-6 received of 200, 400 and 600 mg/kg b.w. EAFFZRB orally, respectively, for 21 days. Group 3 rats received 5 mg/kg b.w Glibenclamide. The effect of EAFFZRB on alterations in hematological, biochemical, and histological indices of study rats were assessed. RESULTS: Extraction of 3500 g ethanol extract yielded 15.71 g EAFFZRB. HPLC fingerprint of EAFFZRB indicated presence of luteolin, rutin, quercetin, apigenin, cinnamic acid and catechin. Diabetes triggered significant (p < 0.05) alterations in b.w., hematological, biochemical and histological indices of test rats relative to normal control. Treatment with EAFFZRB (LD50 = 3807.9 mg/kg b.w.) resulted in remarkable improvements in altered b.w. changes, hematological, biochemical and histological parameters of diabetic rats. CONCLUSION: The study demonstrated the antidiabetic potential of EAFFZRB, providing scientific basis for traditional use of the plant in treatment of diabetes and its complications.

Comparatively analyzing the liver-specific transcriptomic profiles in Kunming mice afflicted with streptozotocin- and natural food-induced type 2 diabetes mellitus.

BACKGROUND: Streptozotocin is a classic drug used to induce diabetes in animal models. OBJECTIVE: The aim of this study is to investigate the liver transcriptome of Kunming mice with diabetes induced by either streptozotocin (STZ) or Non-STZ. METHODS: Forty male mice were randomly assigned into four groups: Control (Ctr, standard diet), mHH (high fat and high carbohydrate diet), mHS (high fat and high carbohydrate diet for 4 weeks followed by 60 mg/kg STZ for 3 consecutive days) and mSH (60 mg/kg STZ for 3 consecutive days followed by a high fat and high carbohydrate diet for 12 weeks). All mice injected with STZ were identified as diabetic despite the sequential feeding of high fat and high carbohydrate diets. RESULTS: Only 7 of 13 mice in the mHH group met the diagnostic criteria for diabetes. The asting blood glucose (FBG) of the mHH, mHS, mSH and Ctrl groups was 13.27 ± 1.14, 15.01 ± 2.59, 15.95 ± 4.38 and 6.28 ± 0.33 mmol/L at the 12th week, respectively. Compared with the mHH group, transcription was elevated in 85 genes in the livers of mHS mice, while 21 genes were downregulated and 97 genes were upregulated in the mSH group while 35 genes were decreased. A total of 43 co-expressed genes were identified in the mHS vs mHH and mSH vs mHH groups. GO (Gene Ontology) and KEGG (Kyoto Encyclopedia of Genes and Genomes) analyses showed that two corporate GO terms and two KEGG pathways were significantly annotated in the STZ-treated groups. Both the GO term and pathway were related to the metabolism mediated by p53. CONCLUSION: A high fat and high carbohydrate diet combined with a low dose of STZ can effectively induce diabetes in Kunming mice despite the abnormal expressions of genes in the liver. The differentially expressed genes were related to metabolism mediated by p53.

Flavonoid-rich fraction of Lasianthera africana leaves alleviates hepatotoxicity induced by carbon tetrachloride in Wistar rats.

Lasianthera africana P. Beauv. (Icacinaceae) is a good source of natural antioxidants, having the potential to protect against oxidative stress-related diseases and complications. This study investigated the antioxidant, hepatoprotective and curative effects of flavonoid-rich fraction of L. africana leaves (LAFRF) against carbon tetrachloride-induced hepatotoxicity in Wistar rats. Phytochemical, nutrient content, and in vitro antioxidant activity of LAFRF were determined by standard methods. Fifty Wistar rats were randomized into 10 groups (n = 5). Groups 1 and 2 served as normal and CCl4 controls, respectively. Groups 3A-6A constituted the protective study while groups 3B-6B represented the curative study. The effects of LAFRF at 3, 10, and 30 mg/kg body weight (b.w.) on lipid peroxidation, antioxidant status, liver enzymes activities, and histology of CCl4-intoxicated rats were assessed. LAFRF total flavonoids (281.05 ± 7.44 mg QE/g), indicated LD50 above 5000 mg/kg b.w., and scavenged ABTS*+ with an IC50 of 5.05 ± 0.00 µg/mL relative to butylated hydroxytoluene (4.16 ± 0.00 µg/mL), and a concentration-dependent increase in total antioxidant capacity. Carbon tetrachloride (1 mL/kg) triggered significant (p < 0.05) increases in malonedialdehyde concentration (2.67 ± 0.21 mg/mL), with a corresponding decline in antioxidant status, and increases in alkaline phosphatase, alanine and aspartate aminotransferase activities (68.00 ± 9.59 IU/L, 79.60 ± 5.03 IU/L and 81.80 ± 3.96 IU/L), respectively. LAFRF significantly (p < 0.05) lowered lipid peroxidation levels, liver enzyme activities, increased antioxidant status, and improved hepatic histo-architecture of pre- and post LAFRF-treated rats. This demonstrates its high antioxidative, hepatoprotective and curative effects, indicating its potential for future drug development.

Bioactive Phytochemicals with Anti-Aging and Lifespan Extending Potentials in Caenorhabditis elegans.

In the forms of either herbs or functional foods, plants and their products have attracted medicinal, culinary, and nutraceutical applications due to their abundance in bioactive phytochemicals. Human beings and other animals have employed those bioactive phytochemicals to improve health quality based on their broad potentials as antioxidant, anti-microbial, anti-carcinogenic, anti-inflammatory, neuroprotective, and anti-aging effects, amongst others. For the past decade and half, efforts to discover bioactive phytochemicals both in pure and crude forms have been intensified using the Caenorhabditis elegans aging model, in which various metabolic pathways in humans are highly conserved. In this review, we summarized the aging and longevity pathways that are common to C. elegans and humans and collated some of the bioactive phytochemicals with health benefits and lifespan extending effects that have been studied in C. elegans. This simple animal model is not only a perfect system for discovering bioactive compounds but is also a research shortcut for elucidating the amelioration mechanisms of aging risk factors and associated diseases.

Gene therapy in PIDs, hemoglobin, ocular, neurodegenerative, and hemophilia B disorders.

A new approach is adopted to treat primary immunodeficiency disorders, such as the severe combined immunodeficiency (SCID; e.g., adenosine deaminase SCID [ADA-SCID] and IL-2 receptor X-linked severe combined immunodeficiency [SCID-X1]). The success, along with the feasibility of gene therapy, is undeniable when considering the benefits recorded for patients with different classes of diseases or disorders needing treatment, including SCID-X1 and ADA-SCID, within the last two decades. ß-Thalassemia and sickle cell anemia are two prominent monogenic blood hemoglobin disorders for which a solution has been sought using gene therapy. For instance, transduced autologous CD34+ HSCs via a self-inactivating (SIN)-Lentivirus (LV) coding for a functional copy of the ß-globin gene has become a feasible procedure. adeno-associated virus (AAV) vectors have found application in ocular gene transfer in retinal disease gene therapy (e.g., Leber's congenital amaurosis type 2), where no prior treatment existed. In neurodegenerative disorders, successes are now reported for cases involving metachromatic leukodystrophy causing severe cognitive and motor damage. Gene therapy for hemophilia also remains a viable option because of the amount of cell types that are capable of synthesizing biologically active FVIII and FIX following gene transfer using AAV vectors in vivo to correct hemophilia B (FIX deficiency), and it is considered an ideal target, as proven in preclinical studies. Recently, the clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR-associated protein 9 gene-editing tool has taken a center stage in gene therapy research and is reported to be efficient and highly precise. The application of gene therapy to these areas has pushed forward the therapeutic clinical application.

Phosphoglucose Isomerase Plays a Key Role in Sugar Homeostasis, Stress Response, and Pathogenicity in Aspergillus flavus.

Aspergillus flavus is one of the important human and plant pathogens causing not only invasive aspergillosis in immunocompromised patients but also crop contamination resulting from carcinogenic aflatoxins (AFs). Investigation of the targeting factors that are involved in pathogenicity is of unmet need to dismiss the hazard. Phosphoglucose isomerase (PGI) catalyzes the reversible conversion between glucose-6-phosphate and fructose-6-phosphate, thus acting as a key node for glycolysis, pentose phosphate pathway, and cell wall biosynthesis in fungi. In this study, we constructed an A. flavus pgi deletion mutant, which exhibited specific carbon requirement for survival, reduced conidiation, and slowed germination even under optimal experimental conditions. The Δpgi mutant lost the ability to form sclerotium and displayed hypersusceptibility to osmotic, oxidative, and temperature stresses. Furthermore, significant attenuated virulence of the Δpgi mutant was documented in the Caenorhabditis elegans infection model, Galleria mellonella larval model, and crop seeds. Our results indicate that PGI in A. flavus is a key enzyme in maintaining sugar homeostasis, stress response, and pathogenicity of A. flavus. Therefore, PGI is a potential target for controlling infection and AF contamination caused by A. flavus.