Iranian Journal of Basic Medical Sciences
Volume:24 Issue: 8, Aug 2021

Depression is a complex heterogeneous brain disorder characterized by a range of symptoms, resulting in psychomotor and cognitive disabilities and suicidal thoughts. Its prevalence has reached an alarming level affecting millions of people globally. Despite advances in current pharmacological treatments, the heterogenicity of clinical response and incidences of adverse effects have shifted research focus to identification of new natural substances with minimal or no adverse effects as therapeutic alternatives. Marine algae-derived extracts and their constituents are considered potential sources of secondary metabolites with diverse beneficial effects. Marine algae with enormous health benefits are emerging as a natural source for discovering new alternative antidepressants. Its medicinal properties exhibited shielding efficacy against neuroinflammation, oxidative stress, and mitochondrial dysfunction, which are indicated to underlie the pathogenesis of many neurological disorders. Marine algae have been found to ameliorate depressive-like symptoms and behaviors in preclinical and clinical studies by restoring monoaminergic neurotransmission, hypothalamic-pituitary-adrenal axis function, neuroplasticity, and continuous neurogenesis in the dentate gyrus of the hippocampus via modulating brain-derived neurotrophic factors and antineuroinflammatory activity. Although antidepressant effects of marine algae have not been validated in comparison with currently available synthetic antidepressants, they have been reported to have effects on the pathophysiology of depression, thus suggesting their potential as novel antidepressants. In this review, we analyzed the currently available research on the potential benefits of marine algae on depression, including their effects on the pathophysiology of depression, potential clinical relevance of their antidepressant effects in preclinical and clinical studies, and the underlying mechanisms of these effects.

The recent pandemics caused by coronavirus infections have become major challenges in 21st century human health. Scientists are struggling hard to develop a complete cure for infectious diseases, for example, drugs or vaccines against these deadly infectious diseases. We have searched papers on thymoquinone (TQ) and its effects on different infectious diseases in databases like Pubmed, Web of Science, Scopus, and Google Scholar, and reviewed them in this study. To date research suggests that natural products may become a potential therapeutic option for their prodigious anti-viral or anti-microbial effects on infectious diseases. TQ, a natural phytochemical from black seeds, is known for its health-beneficial activities against several diseases, including infections. It is evident from different in vitro and in vivo studies that TQ is effective against tuberculosis, influenza, dengue, Ebola, Zika, hepatitis, malaria, HIV, and even recent pandemics caused by severe acute respiratory syndrome of coronaviruses (SARS-CoV and SARS-CoV-2). In these cases, the molecular mechanism of TQ is partly clear but mostly obscure. In this review article, we have discussed the role of TQ against different infectious diseases, including COVID-19, and also critically reviewed the future use of TQ use to fight against infectious diseases.

Accumulated evidence provides a strong connection between the immune system and vascular inflammation. The innate immune system’s main sensors are toll-like receptors (TLRs). Zymosan (Zym), a fungal product, induces an inflammatory response via activating TLR2 of the immune system. Atorvastatin, a potent statin, possesses pleiotropic effects including immunomodulatory, lipid-lowering, and anti-inflammatory. Therefore, the current study aimed to evaluate the protective role of atorvastatin against a high-fat diet (HFD) and Zym-induced vascular inflammation in C57BL/6 mice via modulation of TLR2/NF-ƙB signaling pathway. In silico study was conducted to confirm the binding affinity of atorvastatin against TLR2. Under in vivo study, mice were divided into four groups: Normal control: normal standard chow-diet fed for 30 days + Zym vehicle (sterile PBS, 5 mg/ml on 8th day); HFD (30 days) + Zym (80 mg/kg, IP, on 8th day); HFD/Zym + atorvastatin vehicle (0.5% CMC, p.o., from 10th to 30th day); HFD/Zym + atorvastatin (3.6 mg/kg, p.o., from 10th to 30th day). Atorvastatin treatment along with HFD and Zym inhibited vascular inflammation by suppressing the levels of aortic TLR2, cardiac NF-ƙB and decrease in serum TNF-α and IL-6. Further, there was an increase in hepatic LDLR levels, resulting in a decrease in serum LDL-C and an increase in HDL-C levels. Histopathological examination of the aorta showed a reduction in plaque accumulation with the atorvastatin-treated group as compared with HFD and Zym-treated group. Atorvastatin attenuates vascular inflammation mediated by HFD and Zym through suppression of TLR2, NF-ƙB, TNF-α, IL-6, and upregulation of LDLR levels.

The mitogen-activated protein kinase kinase 4 (MKK4) plays a key role in several processes like inflammation, apoptosis, and tumorigenesis. Several authors have proposed that genetic variations in these genes may alter their expression with subsequent cancer risk. This study aimed to examine the possible association of MKK4 rs3826392 and rs3809728 variants in Mexican patients with colorectal cancer (CRC). These variants were also compared with clinical features as sex, age, TNM stage, and tumor location.

The study included genomic DNA from 218 control subjects and 250 patients. Genotyping of the MKK4 variants was performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) procedure.

Individuals with A/T and T/T genotypes for the rs3809728 (-1044 A>T) variant showed a significantly increased risk for CRC (P=0.012 and 0.007, respectively); while individuals with the G/G genotype for the rs3826392 (-1304 T>G) variant showed a decreased risk for CRC (P=0.012). Genotypes of the MKK4 rs3809728 variant were also significantly related to colon localization and advanced TNM stage in CRC patients. T-T haplotype (rs3826392 and rs3809728) of the MKK4 gene was associated with risk in patients with CRC.

The rs3826392 variant in the MKK4 gene could be a cancer protective factor, while the rs3809728 variant could be a risk factor. These variants play a significant role in CRC risk.

Acrylamide (ACR), has wide uses in different industries. ACR induced several toxicities including neurotoxicity and hepatotoxicity. The probable protective effects of selenium on ACR-induced neurotoxicity and hepatotoxicity in rats were evaluated. Male Wistar rats were studied for 11 days in 8 groups: 1. Control, 2. ACR (50 mg/kg, IP), 3-5. ACR+ selenium (0.2, 0.4, 0.6 mg/kg, IP), 6. ACR+ the most effective dose of selenium (0.6 mg/kg, IP) three days after ACR administration, 7. ACR+ vitamin E (200 mg/kg IP, every other day) 8. Selenium (0.6 mg/kg IP). Finally, behavioral tests were done. The levels of malondialdehyde (MDA), glutathione (GSH), Bcl-2, Bax and caspase 3 proteins in liver and cerebral cortex tissues were measured. Also, the amount of albumin, total protein, alanine transaminase (ALT) and aspartate transaminase (AST) enzymes were determined in serum. ACR caused the severe motor impairment, increased MDA level and decreased GSH content, enhanced Bax/Bcl-2 ratio and caspase 3 proteins in brain and liver tissues. Besides, the level of AST was elevated while the total serum protein and albumin levels were decreased. Administration of selenium (0.6 mg/kg) (from the first day of the experiment and the third day) significantly recovered locomotor disorders, increased GSH content, and reduced MDA level. Also, selenium decreased Bax/Bcl-2 ratio and caspase 3 levels in brain and liver tissues. The oxidative stress and apoptosis pathways have important roles in neurotoxicity and hepatotoxicity of ACR. Selenium significantly reduced ACR-induced toxicity through inhibition of oxidative stress and apoptosis.

Colitis has a high prevalence rate, limited treatment options, and needs to be solved urgently. Application of Licochacone A (LA) or rBMMSCs alone in the treatment of colitis has a certain but limited effect. This study aims to develop an LA-based strategy to improve mesenchymal stem cells’ (MSCs’) therapeutic capacity in mice DSS-induced colitis by increasing the number of MSCs migrating to the inflammation site. In vivo, we injected MSCs pretreated with LA, MSCs alone, or PBS into the tail vein of colitis mice, and assessed the colon length, disease activity index (DAI) score, body weight, HAI score, and tracked the location of MSCs at day 10. In vitro, we knocked down the CXCR4 gene by siRNA and then treated it with LA, then tested the mRNA level of CXCR4 and the migration ability of group CXCR4, CXCR4+LA, LA, and control to verify the relationship between this effect and the SDF-1-CXCR4 signaling pathway. The mice that received LA- pretreated MSCs had ameliorated body weight loss, preserved colon morphology, and decreased DAI and histological activity index (HAI) compared with the MSCs group. Besides, the number of MSCs migrating to the inflammation site significantly increased in group LA+MSCs, and expression of CXCR4 significantly increased too. Furthermore, we found that LA could partly revise the decrease of the migration of MSCs and the expression of CXCR4 mRNA caused by CXCR4-siRNA. LA may improve the migration ability of MSCs through increasing CXCR4 expression therapy enhancing their therapeutic activity.

This study explored Indonesian Actinobacteria which were isolated from Curcuma zedoaria endophytic microbes and mangrove ecosystem for new antimycobacterial compounds. Antimycobacterial activity test was carried out against Mycobacterium tuberculosis H37Rv. Chemical profiling of secondary metabolite using Gas Chromatography-Mass Spectroscopy (GC-MS) and High Resolution-Mass Spectroscopy (HR-MS) was done to the ethyl acetate extract of active strain InaCC A758. Molecular taxonomy analysis based on 16S rRNA gene and biosynthetic gene clusters analysis of polyketide synthase (PKS) and non-ribosomal peptide synthetase (NRPS) from InaCC A758 have been carried out. Bioassay guided isolation of ethyl acetate extract was done, then structural elucidation of active compound was performed using UV-Vis, FT-IR, and NMR spectroscopy methods. The chemical profiling using HR-MS revealed that InaCC A758 has the potential to produce new antimycobacterial compounds. The 16S rRNA gene sequencing showed that InaCC A758 has the closest homology to Streptomyces parvus strain NBRC 14599 (99.64%). In addition, InaCC A758 has NRPS gene and related to S. parvulus (92% of similarity), and also PKS gene related to PKS-type borrelidin of S. rochei and S. parvulus (74% of similarity). Two compounds with potential antimycobacterial were predicted as 1) Compound 1, similar to dimethenamid (C12H18ClNO2S; MW 275.0723), with MIC value of 100 µg/ml, and 2) Compound 2, actinomycin D (C62H86N12O16; MW 1254.6285), with MIC value of 0.78 µg/ml. Actinomycin D has been reported to have antimycobacterial activity, however the compound has been predicted to resemble dimethenamid had not been reported to have similar activity.

High-density lipoprotein (HDL) is necessary for proliferation of several cells. The growth of many kinds of cells, such as breast cancer cells (BCC) is motivated by HDL. Cellular uptake of cholesterol from HDL which increases cell growth is facilitated by scavenger receptors of the B class (SR-BI). The proliferative effect of HDL might be mediated by this receptor. It is also believed that HDL has an anti-apoptotic effect on various cell types and promotes cell growth. This study was designed to investigate SR-BI expression, proliferation and apoptotic effect of HDL on human BCC lines, MCF-7 and MDA-MB-468.

Real-time-PCR method was used to evaluate expression of SR-BI, and cholesterol concentration was measured using a cholesterol assay kits (Pars AZ moon, Karaj, Iran). Cell viability was assessed using the MTT test. To identify cell apoptosis, the annexin V-FITC staining test and caspase-9 activity assay were applied.

Treatment of both cell lines (MCF-7, MDA-MB-468) with HDL results in augmentation of SR-BI mRNA expression and also elevation of the intracellular cholesterol (p <0.01). HDL induced cell proliferation, cell cycle progression, and prevented activation of caspase-9 (p <0.05). We also demonstrated that inhibition of SR-B1 by BLT-1 could reduce cell proliferation, and induction of SR-B1 receptor by quercetin increased HDL-induced proliferation in both cell lines (p <0.05).

It can be concluded that alteration in HDL levels by SR-B1 activator (Quercetin) or inhibitor (BLT-1) may affect BCC growth and apoptosis induction.

This study aimed to evaluate the role of miR-146a-5p in the pathogenesis of diabetic retinopathy and its interaction with oxidative stress and inflammation in the ocular tissue of rats with type 2 diabetes mellitus (T2DM). Twenty adult male Sprague Dawley rats (220 ±20 g) were randomly assigned to control and diabetic groups. A high-fat diet was used for three months to induce T2DM which was confirmed by the HOMA-IR index. After that, the levels of glucose and insulin in serum, HOMA-IR as an indicator of insulin resistance, the ocular level of oxidative markers, TNF‐α, IL-1β, MIPs, and MCP-1 along with ocular gene expression of NF-κB, Nrf2, and miR-146a-5p were evaluated. The level of lipid peroxidation along with metabolic and inflammatory factors significantly increased and the antioxidant enzyme activity significantly decreased in diabetic rats (p <0.05). The ocular expression of NF-κB and TNF-α increased and Nrf2, HO-1, and miR-146a-5p expression decreased in diabetic rats (p <0.05). In addition, a negative correlation between miR-146a-5p expression with NF-κB and HOMA-IR and a positive correlation between miR-146a-5p with Nrf2 were observed. It can be concluded that miR-146a-5p may regulate Nrf2 and NF-κB expression and inflammation and oxidative stress in the ocular tissue of diabetic rats.

The protective effect of ethyl acetate fraction (EAF) of Boerhavia diffusa roots against Tacrolimus (TAC) induced nephrotoxicity was studied using MDCK cell lines. Ethanolic root extract of B. diffusa was fractionated using the liquid-liquid partition method. The cytotoxic effect of TAC and protective effect of EAF co-treatment were studied in MDCK cell lines by measuring ROS, LPO, and NO levels; collagen accumulation, effect on mitochondrial membrane integrity and cell cycle analysis were studied. The active component in EAF was quantified by HPLC analysis. TAC induced toxicity, leading to apoptosis and necrosis, was significantly reduced (p <0.001) in EAF co-treatment, with reversal of cell cycle arrest and reduced cell population at sub G0/G1 phase. Further, ROS (p <0.05), LPO and NO (p <0.001), were significantly reduced with EAF co-treatment compared with TAC individually treated cells. TAC induced mitochondrial membrane integrity loss was found to be significantly reduced in co-treated cells, as measured by rhodamine123 (p <0.05) and translocation of cytochrome c (p <0.001) from nucleus to cytoplasm, and caspase 3 release (p <0.001). The same was confirmed through annexin-FITC and PI staining (p <0.05) with reduced apoptotic and necrotic death in co-treated population. Interestingly, EAF co-treatment decreased collagen accumulation (p <0.001) with significant increase in the cell survival of tubular epithelial cells. HPLC analysis showed the presence of Quercetin (87.5 mg/g) in EAF, which may be responsible for the nephroprotective role. Thus, these results provide sound evidence that EAF may be an effective adjuvant therapy to prevent nephrotoxicity induced by TAC.

Catheters are one of the factors for complicated urinary tract infections. Uropathogenic bacteria can attach to the catheter via cell surface hydrophobicity (CSH), form biofilms, and remain in urinary tract. The study was evaluated phenotypic and genotypic characteristics of fimbriae in Klebsiella pneumoniae and uropathogenic Escherichia coli (UPEC) isolates from patients with catheter-associated urinary tract infections (CAUTIs) and their association with biofilm formation. Urine specimens were collected through catheters in patients with CAUTIs. Sixty bacterial isolates were identified by biochemical tests. For determination of biofilm formation a tissue culture plate was used. Microbial adhesion to hydrocarbons (MATH) was conducted for CSH determination. The mannose-sensitive haemagglutination (MSHA) and mannose-resistant haemagglutination (MRHA) were determined for type 1 and type 3 fimbriae. Finally, the presence of genes encoding fimbriae was determined by PCR. All isolates showed strong CSH, biofilm capacity and MRHA phenotype. The results showed that 20% of UPEC and 23% of K. pneumoniae isolates contained MSHA phenotypes. There was a significant association between biofilm formation and MSHA phenotype in UPEC isolates. The frequency of fimA (80%) and fimH (96.6%) in K. pneumoniae isolates was higher than UPEC isolates. Both types of bacterial isolates with MSHA phenotypes harbored the fimH gene. The phenotypic and genotypic characteristics of two bacterial species were highly similar. Also, the type of fimbriae affected bacterial biofilm formation through catheterization. It seems that fimH and mrk gene cluster subunits are suitable markers for identifying bacterial pathogenesis.

Chemerin is associated with insulin resistance, obesity, and metabolic syndrome. α-lipoic acid (α-LA) is a potent antioxidant involved in the reduction of diabetic symptoms. This study aimed to investigate the relationship between chemerin and P38 MAPK in the progression of diabetic nephropathy (DN) and examine the effects of α-LA on chemerin-treated human mesangial cells (HMCs). HMCs were transfected with a chemerin-overexpressing plasmid. HMCs were also treated with high-glucose, chemerin, α-LA, PDTC (pyrrolidine dithiocarbamate ammonium, NF-κB p65 inhibitor), and/or SB203580 (P38 MAPK inhibitor). Cell proliferation was tested using the Cell Counting Kit-8 assay. Collagen type IV and laminin were tested by ELISA. Chemerin expression was detected by qRT-PCR. The chemerin receptor was detected by immunohistochemistry. Interleukin-6 (IL-6), tumor necrosis factor-a (TNF-α), nuclear factor-κBp-p65 (NF-κB p-p65), transforming growth factor-β (TGF-β), and p-P38 mitogen-activated protein kinase (p-P38 MAPK) were evaluated by western blot. High-glucose culture increased the expression of the chemerin receptor. α-LA inhibited HMC proliferation. Chemerin overexpression increased collagen type IV and laminin expression. P38 MAPK signaling was activated by chemerin, resulting in up-regulation of IL-6, TNF-α, NF-κB p-p65, and TGF-β. SB203580, PDTC, and α-LA reversed the effects of chemerin, reducing IL-6, TNF-α, NF-κB p-p65, and TGF-β expression. Chemerin might be involved in the occurrence and development of DN. α-LA might prevent the effects of chemerin on the progression of DN, possibly via the P38 MAPK pathway.

Foodborne diseases are considered as an important public health issue. The purpose of the current study was to isolate Lactobacillus spp. strains from fecal samples, investigate their antimicrobial properties, and assess the expression of genes encoding bacteriocin in co-culture of Lactobacillus with enteric pathogens. Fecal samples of healthy people were collected. Human colon adenocarcinoma cell line Caco-2 was used to examine Lactobacillus strains adherence capacity. Quantitative real-time reverse transcription PCR (qRT-PCR) was used to determine bacteriocin-encoding genes expression in co-culture of the selected Lactobacillus strain with Salmonella, Shigella, and two diarrheagenic Escherichia coli serotypes during 4, 6, and 24 hr of incubation. The selected L. plantarum strain was able to inhibit four foodborne pathogens in both methods. L. plantarum No.14 exhibited the highest ability to adhere to Caco-2 cells. In this study, pln F, sak P, pln I, pln B, and pln J genes of L. plantarum No.14 were upregulated in co-culture of L. plantarum No.14 with diarrheagenic E. coli serotypes. In addition, acd, Lactacin F, sak P, pln J, pln EF, and pln NC8 genes as well as pln NC8 and pln A genes mRNA levels were significantly increased in co-culture of L. plantarum No.14 with Shigella dysenteriae, and Salmonella typhi, respectively, during 24 hrs of incubation. Other studied genes were down-regulated during the incubation time. The selected L. plantarum strains could be served as alternative antimicrobial agents against pathogens which could contaminate foodstuffs and are responsible for human diseases.

Prevalence of influenza virus, creates the need to achieve an efficient vaccine against it. We examined whether the predicted antigenic epitopes of HA, NP, and M2 proteins of the influenza H1N1 and H3N2 viruses accompanied by chitin and chitosan biopolymers might be relevant to the induction of effective proper mucosal responses. The construct was prepared using B and T cell predicted epitopes of HA, NP, and M2 proteins from the influenza H1N1 and H3N2 viruses by considering haplotype “d” as a dominant allele in the BALB/c mice. Intranasal immunization with purified LPS free recombinant protein together with chitin and chitosan microparticles as adjuvants was administered at an interval of 2 weeks in thirty-five BALB/c female mice which were divided into seven groups. Ten days after the last immunization, humoral and cellular immune responses were examined. Elevated systemic IgG2a, IgA, and mucosal IgA revealed a humoral response to the construct. An increase in the number of IFN-γ-producing cells in re-stimulation of splenocytes in the culture medium by poly-tope as well as rise in the concentrations of IL-6, IL-17, and TNF-α along with the regulatory response of IL-10, presented the capacity of the designed protein to provoke significant immune responses. The neutralization test ultimately confirmed the high efficacy of the protein in inhibiting the virus. The results support the fact that immunogenic poly-tope protein in the presence of chitin and chitosan microparticles as mucosal adjuvants is able to induce humoral and cell-mediated responses in BALB/c mice.

Ginkgo biloba leaf extract (EGb-761) injection has been widely used as adjuvant therapy for cerebral stroke in China. However, its underlying pharmacological mechanism is not completely understood. The present study aimed to investigate whether the therapeutic effects of EGb-761 are exerted by modulating autophagy flux. Ischemic cerebral stroke was prepared in male Sprague-Dawley rats by middle cerebral artery occlusion (MCAO) followed by reperfusion. The MCAO/reperfusion rats were then treated with EGb-761 injection once daily for 7 days. Thereafter, the brain tissues in the ischemic penumbra were obtained to detect the key proteins in the autophagic/lysosomal pathway with Beclin1, LC3, (SQSTM1)/p62, ubiquitin, LAMP-1, cathepsin B, and cathepsin D antibodies by western blot and immunofluorescence. Meanwhile, the infarct volume, neurological deficits, and neuronal apoptosis were assessed to evaluate the therapeutic outcomes. The results illustrated that EGb-761 treatment was not only able to promote the autophagic activities of Beclin1 and LC3-II in neurons, but also could enhance the autophagic clearance, as indicated by reinforced lysosomal activities of LAMP-1, cathepsin B, and cathepsin D, as well as alleviating autophagic accumulation of ubiquitin and insoluble p62 in the MCAO+EGb-761 group, compared with those in the MCAO+saline group. Meanwhile, cerebral ischemia-induced neurological deficits, infarct volume, and neuronal apoptosis were significantly attenuated by 7 days of EGb-761 therapy. Our data suggest that EGb-761 injection can elicit a neuroprotective efficacy against MCAO/reperfusion injury, and this neuroprotection may be exerted by enhancement of autophagy flux in neurons in the ischemic penumbra.

Protective effects of s-methyl cysteine (SMC) alone, protocatechuic acid (PCA) alone, and SMC plus PCA against chronic ethanol consumption induced hepatic steatosis and inflammation were investigated.  

Mice were divided into six groups: normal diet (ND) group, Lieber-DeCarli liquid diet without ethanol (LD diet) group, LD diet with ethanol (LED diet) group, SMC group (LED diet plus 0.25% SMC), PCA group (LED diet plus 0.25% PCA), and SMC+PCA group (LED diet plus 0.125% SMC + 0.125% PCA).  After 8 weeks of supplementation, blood and liver were used for analysis.  

Biochemical and histological data showed that SMC plus PCA led to a greater reduction in lipid droplets in the liver than SMC or PCA treatment alone.  SMC plus PCA resulted in greater suppression in hepatic mRNA expression of peroxisome proliferator-activated receptor-gamma, sterol regulatory element-binding protein 1c, stearoyl-CoA desaturase-1, cyclooxygenase-2, and myeloperoxidase than SMC or PCA treatment alone.  SMC plus PCA led to a greater decrease in hepatic reactive oxygen species and inflammatory cytokine levels than SMC or PCA treatment alone.  

These novel findings suggest that the combination of SMC and PCA was a potent remedy for alcoholic liver disorders.

Duchene muscular dystrophy (DMD) is a progressive neuromuscular disease caused by mutations in the DMD gene, resulting in the absence of dystrophin expression leading to membrane fragility and myofibril necrosis in the muscle cells. Because of progressive weakness in the skeletal and cardiac muscles, premature death is inevitable.  There is no curative treatment available for DMD. In recent years, advances in genetic engineering tools have made it possible to manipulate gene sequences and accurately modify disease-causing mutations. CRISPR/Cas9 technology is a promising tool for gene editing because of its ability to induce double-strand breaks in the DNA.

In this study for the exon-skipping approach, we designed a new pair of guide RNAs (gRNA) to induce large deletion of exons 48 to 53 in the DMD gene in the human skeletal muscle cell line (HSkMC), in order to correct the frame of the gene.

Data showed successful editing of DMD gene by deletion of exons 48 to 53 and correction of the reading frame in edited cells. Despite a large deletion in the edited DMD gene, the data of real-time PCR, immune florescent staining demonstrated successful expression of truncated dystrophin in edited cells.

This study demonstrated that the removal of exons 48-53 by the CRISPR / Cas9 system did not alter the expression of the DMD gene due to the preservation of the reading frame of the gene.