Proteins with Anti-apoptotic Action in the Hemolymph of Caterpillars of the Megalopygidae Family Acts by Maintaining the Structure of the Cellular Cytoskeleton.

Brazil has a very large biological variety, which is an almost inexhaustible source of substances of pharmacological and biotechnological interest. Several studies have demonstrated the presence of bioactive peptides in insect hemolymph and their potential use as therapeutic agents. However, few data are available regarding molecules extracted from insects with anti-apoptotic action. The objective of this work was to identify the presence of proteins from the hemolymph of caterpillars of the Megalopygidae family with pharmacological and biotechnological interest. This study provides preliminary and innovative information on a new substance that inhibits cellular apoptopsis and stabilizes the tested cells, impacting the cytoskeleton, maintaining cellular structure and its functions. To this, two species of Megalopygidae family were studied, Podalia sp. and Megalopyge albicolis. Cytotoxicity tests on Vero and Sf-9 cells revealed that the hemolymph of both caterpillars was cytotoxic only at concentrations greater than 5%v/v. In the anti-apoptotic activity assays, it was verified that the supplementation of cell cultures with only 1% of hemolymph v/v is sufficient to inhibit cell death by apoptosis induced by different inducers such as terbutyl, actinomycin D, hydrogen peroxide, or even by nutrient depletion. For this study, cells were stained with trypan blue, crystal violet, and fluorescent markers to cytoskeleton (actin and tubulin), mitochondria membrane electric potential (JC-1), and apoptosis marker (acridine orange and ethidium). The protein responsible for anti-apoptotic action was isolated through gel filtration chromatography, using an AKTA purifier high-resolution liquid chromatography system. The hemolymph was fractionated into 3 pools for Podalia sp. and 6 pools for M. abicolis. In the antiapoptotic tests, semi-purified hemolymph from both caterpillars showed anti-apoptotic effect in VERO and SF-9 cells, pre-treated with only 1% v/v of hemolymph and induced to death by different and apoptotic inductors. Was observed that the molecule with anti-apoptotic effect is present in pool 3 in both hemolymphs. This protector effect blocked and attenuated the disruption of the cytoskeleton (actin filaments), being that the protective effect also was observed on the integrity of the mitochondrial membrane of SF-9 cells pre-treated with both hemolymphs and treated with the apoptosis inducer Terbutil at concentrations of 25 to 100 µM. By acting on the mitochondrial pathway of death by apoptosis, and by maintaining the structure of the cytoskeleton and cellular functions, pathway that can cause disorders and diseases neurodegenerative, the substances present in the hemolymph of these and other caterpillars could be good candidates in studies for the treatment of neurodegenerative diseases such as Parkinson's disease and Alzheimer's.

Proteins with anti-apoptotic action in the hemolymph of caterpillars of the Megalopygidae family acts by maintaining the structure of the cellular cytoskeleton

Brazil has a very large biological variety, which is an almost inexhaustible source of substances of pharmacological and biotechnological interest. Several studies have demonstrated the presence of bioactive peptides in insect hemolymph and their potential use as therapeutic agents. However, few data are available regarding molecules extracted from insects with anti-apoptotic action. The objective of this work was to identify the presence of proteins from the hemolymph of caterpillars of the Megalopygidae family with pharmacological and biotechnological interest. This study provides preliminary and innovative information on a new substance that inhibits cellular apoptopsis and stabilizes the tested cells, impacting the cytoskeleton, maintaining cellular structure and its functions. To this, two species of Megalopygidae family were studied, Podalia sp. and Megalopyge albicolis. Cytotoxicity tests on Vero and Sf-9 cells revealed that the hemolymph of both caterpillars was cytotoxic only at concentrations greater than 5%v/v. In the anti-apoptotic activity assays, it was verified that the supplementation of cell cultures with only 1% of hemolymph v/v is sufficient to inhibit cell death by apoptosis induced by different inducers such as terbutyl, actinomycin D, hydrogen peroxide, or even by nutrient depletion. For this study, cells were stained with trypan blue, crystal violet, and fluorescent markers to cytoskeleton (actin and tubulin), mitochondria membrane electric potential (JC-1), and apoptosis marker (acridine orange and ethidium). The protein responsible for anti-apoptotic action was isolated through gel filtration chromatography, using an AKTA purifier high-resolution liquid chromatography system. The hemolymph was fractionated into 3 pools for Podalia sp. and 6 pools for M. abicolis. In the antiapoptotic tests, semi-purified hemolymph from both caterpillars showed anti-apoptotic effect in VERO and SF-9 cells, pre-treated with only 1% v/v of hemolymph and induced to death by different and apoptotic inductors. Was observed that the molecule with anti-apoptotic effect is present in pool 3 in both hemolymphs. This protector effect blocked and attenuated the disruption of the cytoskeleton (actin filaments), being that the protective effect also was observed on the integrity of the mitochondrial membrane of SF-9 cells pre-treated with both hemolymphs and treated with the apoptosis inducer Terbutil at concentrations of 25 to 100 µM. By acting on the mitochondrial pathway of death by apoptosis, and by maintaining the structure of the cytoskeleton and cellular functions, pathway that can cause disorders and diseases neurodegenerative, the substances present in the hemolymph of these and other caterpillars could be good candidates in studies for the treatment of neurodegenerative diseases such as Parkinson’s disease and Alzheimer’s.

The Radioprotective Potentials of Silymarin/Silibinin Against Radiotherapy- Induced Toxicities: A Systematic Review of Clinical and Experimental Studies.

BACKGROUND: Although radiotherapy is one of the main cancer treatment modalities, exposing healthy organs/tissues to ionizing radiation during treatment can lead to different adverse effects. In this regard, it has been shown that the use of radioprotective agents may alleviate the ionizing radiation-induced toxicities. OBJECTIVE: The present study aims to review the radioprotective potentials of silymarin/silibinin in the prevention/reduction of ionizing radiation-induced adverse effects on healthy cells/tissues. METHODS: Based on PRISMA guidelines, a comprehensive and systematic search was performed for identifying relevant literature on the "potential protective role of silymarin/silibinin in the treatment of radiotherapy-induced toxicities" in the different electronic databases of Web of Science, PubMed, and Scopus up to April 2022. Four hundred and fifty-five articles were obtained and screened in accordance with the inclusion and exclusion criteria of the current study. Finally, 19 papers were included in this systematic review. RESULTS: The findings revealed that the ionizing radiation-treated groups had reduced survival rates and body weight in comparison with the control groups. It was also found that radiation can induce mild to severe adverse effects on the skin, digestive, hematologic, lymphatic, respiratory, reproductive, and urinary systems. Nevertheless, the administration of silymarin/silibinin could mitigate the ionizing radiation-induced adverse effects in most cases. This herbal agent exerts its radioprotective effects through anti-oxidant, anti-apoptosis, anti-inflammatory activities, and other mechanisms. CONCLUSION: The results of the current systematic review showed that co-treatment of silymarin/silibinin with radiotherapy alleviates the radiotherapy-induced adverse effects in healthy cells/tissues.

Neuroprotective effects of erythropoietin on neurodegenerative and ischemic brain diseases: the role of erythropoietin receptor.

Erythropoietin (Epo) is a fundamental hormone in the regulation of hematopoiesis, and other secondary roles mediated by the binding of the hormone to its specific receptor (EpoR), which leads to an activation of key signaling pathways that induce an increase in cell differentiation, apoptosis control and neuroprotection. It has been suggested that their function depends on final conformation of glycosylations, related with affinity to the receptor and its half-life. The presence of EpoR has been reported in different tissues including central nervous system, where it has been demonstrated to exert a neuroprotective function against oxidative stress conditions, such as ischemic injury and neurodegenerative diseases. There is also evidence of an increase in EpoR expression in brain cell lysates of Alzheimer's patients with respect to healthy patients. These results are related with extensive in vitro experimental data of neuroprotection obtained from cell lines, primary cell cultures and hippocampal slices. Additionally, this data is correlated with in vivo experiments (water maze test) in mouse models of Alzheimer's disease where Epo treatment improved cognitive function. These studies support the idea that receptor activation induces a neuroprotective effect in neurodegenerative disorders including dementias, and especially Alzheimer's disease. Taken together, available evidence suggests that Epo appears to be a central element for EpoR activation and neuroprotective properties in the central nervous system. In this review, we will describe the mechanisms associated with neuroprotection and its relation with the activation of EpoR in order with identify new targets to develop pharmacological strategies.