Myricetin loaded in solid lipid nanoparticles induces apoptosis in the HT-29 colorectal cancer cells via mitochondrial dysfunction

BACKGROUND

Among the flavonoids, Myricetin (MCN) has negligible side effects and anti-cancer properties. However, the therapeutic potential of MCN has been limited mainly by its low bioavailability. Nanocarriers improve the bioavailability and stability of flavonoids. The toxic effects of MCN loaded in solid lipid nanoparticles (MCN-SLNs) on the HT-29 human colorectal cancer cells were investigated in this study.

METHODS AND RESULTS

HT-29 cells were exposed to the 30 µmol MCN or MCN-SLNs for 24 h. Colony formation, cell viability, apoptosis, and expression of the Bax, Bcl-2, and AIF (apoptosis-inducing factor) have been investigated. Mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) generation were also measured. The MCN-SLNs with appropriate characteristics and a slow sustained MCN release until 48 h made. MCN-SLNs could diminish colony numbers and survival of the HT-29 cells. The apoptosis index of MCN-SLNs-treated cells significantly increased compared to the free MCN (p < 0.001). The expression of Bax and AIF were elevated (p < 0.01 and p < 0.001, respectively) while Bcl-2 expression was decreased in MCN-SLNs treatment (p < 0.05). Moreover, MCN-SLNs significantly enhanced the ROS formation and reduced MMP compared to the free MCN-treated cells (p < 0.01).

CONCLUSIONS

The SLN formulation of MCN can effectively induce colon cancer cell death by raising ROS formation and activating the apoptosis process.

Protective effects of selenium on Bisphenol A-induced oxidative stress in mouse testicular mitochondria and sperm motility

OBJECTIVE

This study aimed to explore the impact of selenium (SE) on Bisphenol-A (BPA)-exposed sperm and isolated testicular mitochondria of mice.

METHODS

Mouse sperm and isolated mitochondria were exposed to BPA (0.8 mM) and different concentrations of SE (50, 100, and 200 μM) for four hours. The viability of sperm and isolated mitochondria as well as the mitochondrial membrane potential (MMP) were evaluated. SOD (superoxide dismutase), GSH (glutathione), MDA (malondialdehyde), and ROS (reactive oxygen species) levels in testicular mitochondria were also examined.

RESULTS

BPA concentration-dependently enhanced ROS and MDA levels in isolated mitochondria, while MMP and acclivity of GSH and SOD significantly reduced. BPA also considerably impaired spermatozoa survival and motility. SE concentration-dependently reduced mitochondrial oxidative stress, MMP, sperm survival, and total sperm motility.

CONCLUSIONS

Our findings collectively suggested that SE concentration-dependently reversed BPA-caused mitochondrial toxicity and reduced sperm motility by suppressing oxidative stress.

The Dual Role of ROS in Hematological Malignancies: Stem Cell Protection and Cancer Cell Metastasis

BACKGROUND AND OBJECTIVE

Reactive oxygen species (ROS) play crucial role in hematopoiesis, regulation of differentiation, self-renewal, and the balance between quiescence and proliferation of hematopoietic stem cells (HSCs). The HSCs are a small population of undifferentiated cells that reside in the bone marrow (BM) and can undergo self-renewal by giving rise to mature cells.

METHODS

Relevant literature was identified through a PubMed search (2000-2019) of English-language papers using the following terms: reactive oxygen species, hematopoietic stem cell, leukemic stem cell, leukemia and chemotherapy.

RESULTS

HSCs are very sensitive to high levels of ROS and increased production of ROS have been attributed to HSC aging. HSC aging induced by both cell intrinsic and extrinsic factors is linked to impaired HSC self-renewal and regeneration. In addition, the elevated ROS levels might even trigger differentiation of Leukemic stem cells (LSCs) and ROS may be involved in the initiation and progression of hematological malignancies, such as leukemia.

CONCLUSION

Targeting genes involved in ROS in LSCs and HSCs are increasingly being used as a critical target for therapeutic interventions. Appropriate concentration of ROS may be an optimal therapeutic target for treatment of leukemia during chemotherapy, but still more studies are required to better understanding of the of ROS role in blood disorders.

Taurine attenuates valproic acid-induced hepatotoxicity via modulation of RIPK1/RIPK3/MLKL-mediated necroptosis signaling in mice

Valproic acid (VPA) is known as a common drug in seizure and bipolar disorders treatment. Hepatotoxicity is the most important complication of VPA. Taurine (Tau), an amino acid, has antioxidant effects. The present research was conducted to evaluate the protective mechanisms of Tau on VPA-induced liver injury, especially focusing on the necroptosis signaling pathway. The sixty-four male NMRI mice were divided into eight groups with eight animals per each. The experiment groups pretreated with Tau (250, 500, 1000 mg/kg) and necrostatine-1 (Nec-1, 1.8 mg/kg) and then VPA (500 mg/kg) was administered for 14 consecutive days. The extent of VPA-induced hepatotoxicity was confirmed by elevated ALP (alkaline phosphatase), AST (aspartate aminotransferase), ALT (alanine aminotransferase) levels, and histological changes as steatosis, accumulation of erythrocytes, and inflammation. Additionally, VPA significantly induced oxidative stress in the hepatic tissue by increasing ROS (reactive oxygen species) production and lipid peroxidation level along with decreasing GSH (glutathione). Hepatic TNF-α (tumor necrosis factor) level, mRNA and protein expression of RIPK1 (receptor-interacting protein kinase 1), RIPK3, and MLKL (mixed lineage kinase domain-like pseudokinase) were upregulated. Also, the phosphorylation of MLKL and RIPK3 increased in the VPA group. Tau could effectively reverse these events. Our data suggest which necroptosis has a key role in the toxicity of VPA through TNF-α-mediated RIPK1/RIPK3/MLKL signaling and oxidative stress. Our findings suggest that Tau protects the liver tissue against VPA toxicity via inhibiting necroptosis signaling pathway mediated by RIPK1/RIPK3/MLKL and suppressing oxidative stress, and apoptosis.

Taurine effects on Bisphenol A-induced oxidative stress in the mouse testicular mitochondria and sperm motility

Objectives:

This study was performed to investigate the protective effects of taurine (2-aminoethanesulfonic acid, TAU) on oxidative stress in the isolated mouse testicular mitochondria, mitochondrial membrane potential (MMP), viability and motility of the exposed sperms to the BPA.

Methods:

We treated epididymal spermatozoa obtained from mice and isolated mouse testicular mitochondria with BPA (0.8 mmol/mL) and various doses of TAU (5, 10, 30 and 50 µmol/L). We used the MTT assay and Rhodamine 123 uptake to assess sperm viability and MMP. We assessed the oxidative stress through measuring ROS (reactive oxygen species), MDA (malondialdehyde), GSH (glutathione), and SOD (super-oxide dismutase) levels in the testicular mitochondrial tissue.

Results:

BPA significantly elevated ROS, MDA and MMP levels, and markedly reduced SOD and GSH levels in the isolated mitochondria. BPA also considerably impaired spermatozoa viability and motility. Pretreatment with 30 and 50 µmol/L of TAU could considerably suppressed mitochondrial oxidative stress, enhanced MMP, and improved sperm motility and viability.

Conclusion:

TAU may attenuate the BPA-induced mitochondrial toxicity and impaired sperm motility via decreasing oxidative stress.

Effects of Wharton's jelly mesenchymal stem cells-derived secretome on colon carcinoma HT-29 cells

Secreted factors (secretome) of Wharton's jelly mesenchymal stem cells (WJMSCs) have therapeutic impacts. This study was conducted to investigate the impact of WJMSCs-derived secretome (WJMSCs-Se) in apoptosis and the growth of HT-29 cells. HT-29 cells treated with 25 or 50 μg/mL WJMSCs-Se for 24 h. Colony formation and MTT test was used to assess the proliferation and cytotoxicity of the HT-29 cells. Annexin V/PI staining was done for the assessment of apoptosis. The mRNA expression of important apoptosis-related genes was also examined. In the WJMSCs-Se-treated HT-29 cells, colony numbers and viability percentages were significantly reduced in a concentration-dependent manner. Apoptotic and necrotic indexes of WJMSCs-Se-treated HT-29 cells considerably enhanced in comparison to the control. The Caspase-9 and -3 activities were significantly increased in the WJMSCs-Se-exposed HT-29 cells. The mRNA expression of Caspase-9, Caspase-3, and Bax/ Bcl-2 ratio was considerably elevated in the WJMSCs-Se-treated HT-29 cells. Caspase-8 activity and expression of the p53 gene were not affected by the WJMSCs-Se. Taken together, we concluded that WJSCs-Se significantly prevented cell growth and enhanced colon cancer cell death in a concentration-dependent manner mainly through the intrinsic apoptotic pathway.

Microarray analysis of apoptosis gene expression in liver injury induced by chronic exposure to arsenic and high-fat diet in male mice

Rapid growth in the incidence of liver disease is largely attributable to lifestyle and environmental contaminants, which are often overlooked as the leading causes of this problem. Thus, the possible contribution of arsenic (As) to high-fat diet (HFD)-induced liver damage was examined via microarray analysis. To perform this experiment, a total number of 40 healthy adult male NMRI mice (22-30 g) were used. To this end, these animals were randomly assigned to four groups of 10. Oxidative stress and histopathological parameters were also evaluated in the liver of the mice exposed to a minimally cytotoxic concentration of As (50 ppm) in drinking water while being fed with a HFD for 20 weeks. Subsequently, apoptosis gene expression profiling was utilized via real-time (RT) PCR array analysis. The results showed that As had increased the amount of HFD-induced liver damage and consequently amplified changes in oxidative stress factors, histopathological parameters, as well as apoptosis pathway genes. Investigating the expression profile of apoptosis pathway genes similarly revealed that caspase-8, as a main upstream contributor to the apoptosis pathway, might play an important role in the induction of apoptosis generated by As and HFD. Ultimately, this study highlighted that As in drinking water could increase sensitivity in mice to HFD-induced liver disease through strengthening apoptosis pathway.

Effects of Quercetin on Tubular Cell Apoptosis and Kidney Damage in Rats Induced by Titanium Dioxide Nanoparticles

Background

Recent studies have demonstrated that many nanoparticles have an adverse or toxic effect on the kidney.

Objective

To investigate the nephroprotective effect of quercetin (QT) against renal injury induced by titanium dioxide nanoparticles (NTiO2) in rats.

Methods

NTiO₂-intoxicated rats received 50 mg/kg of NTiO₂ for seven days. The QT + NTiO₂ group was pretreated with QT for seven days before being administered NTiO₂. Uric acid, creatinine, and blood urea nitrogen were considered to be biomarkers of nephrotoxicity. Catalase (CAT) and superoxide dismutase (SOD) activities and renal levels of malondialdehyde (MDA) were measured to assess the oxidative stress caused by NTiO₂.

Results

NTiO₂ significantly increased the plasma level of the biomarkers. It also significantly decreased the activities of CAT (P = 0.008) and SOD (P = 0.004), and significantly increased the MDA levels (P = 0.007). NTiO₂ caused proximal tubule damage, the accumulation of red blood cells, the infiltration of inflammatory cells, and reduced the glomerular diameters, as well as induced apoptosis in the proximal tubules. Pre-treatment with QT attenuated the histological changes, normalised the plasma biomarkers, suppressed oxidative stress, ameliorated the activities of CAT (P = 0.007) and SOD (P = 0.006), and reduced apoptosis (P < 0.001).

Conclusion

QT was found to have a potent protective effect against nephrotoxicity induced by NTiO₂ in rats. It also reduced apoptosis caused by NTiO₂.

Determination of carbon/nitrogen ratio and heavy metals in bulking agents used for sewage composting

Improving the soil quality with organic matter and N, P and K contents are some of sewage sludge benefits. Adjusting carbonaceous materials such as plant wastes to dewatered sludge compost results in increasing the moisture content and improving C/N ratio. This study was conduced for three months in 2005, in Laboratory of Chemistry of Water and Wastewater in the School of Public Health of Isfahan University of Medical Science, to determine the C/N ratio and heavy metals concentration of bulking agents in sawdust, leaves, rice hulls and dewatered sewage sludge. Dewatered sludge was collected from Isfahan sewage treatment plant. Sawdust was collected from sawmills. Leaves were collected from municipality of Isfahan and rice hull from rice mills, then in samples determined C/N ratio and heavy metal according to standard methods. The results showed that concentrations of chromium and cadmium in the mixture of dewatered sewage sludge and bulking agents were lower them those of the standard level. Means of cobalt (115.44 mg kg(-1)), nickel (57.44 mg kg(-1)) and zinc (273.48 mg kg(-1)) concentrations were maximum in dewatered sludge but mean concentration of cobalt (25.66 mg kg(-1)) in rice hull samples and mean zinc (8.99 mg kg(-1)) and nickel (5.106 mg kg(-1)) concentrations in sawdust samples were minimum. The optimal conditions sewage sludge composting, each kilogram of sludge needs 350 g of saw dust, 470 g of leaves and 388 g of rice hull. Amount of heavy metals present in the bulking agents is lower than the amount mentioned for the compost.

Combined compost and vermicomposting process in the treatment and bioconversion of sludge

Traditional thermophillic composting is commonly for treatment of sludge. A related technique as vermicomposting process, using earthworms to breakdown sludge, is also becoming popular. These two techniques have their inherent advantages and disadvantages. The combined approach suggested in this study to enhance the overall process and improve the products qualities. Two systems, vermicomposting and combined compost-vermicomposting processes, have been investigated in this study. The sludge used in this study was obtained from the drying beds of South Isfahan wastewater treatment plant. The sludge mixed with sawdust to provide C/N ratio of 25/1. Eisenia fetida was the species of earthworms used in the vermicomposting processes. The results obtained indicate reduction in the amount of volatile solids, total carbon and C/N ratio with the vermicompost age, which indicates the reduction in the biodegradable organic content and mineralization of sludge. Also increase in phosphorus concentration by the end process because of mineralization of organic matter. The results indicate that, a system that combines the two mentioned processes not only shortens stabilization time, but also improves the products quality. Combining the two systems resulted in a product that was more stable and homogenous; the product could meet the pathogen reduction requirements.