Biological Sciences

Many studies have shown the positive effect of laser radiation and application of the mesenchymal stem cells (MSCs) and their secretion in stimulating bone regeneration. The aim of this study was determining effects of MSC conditioned media (CM) and low-level laser (LLL) on healing bone defects in the hypothyroid male rat. Methods: We assigned 30 male Wistar rats randomly to 3 groups: control, hypothyroidism, CM+LLL. Four weeks after surgery, the right tibia was removed. Biomechanical examination and histological examinations were performed immediately. Results: Our results showed significant increase in bending stiffness (116.09 ± 18.49), maximum force (65.41 ± 8.16), stress high load (23.30 ± 7.14), energy absorption (34.57 ± 4.10), trabecular bone volume (1.34 ± 0.38) and the number of osteocyte, osteoblast, and osteoclast (12.77 ± 0.54, 6.19 ± 0.80, 1.12 ± 0.16 respectively) in osteotomy site in the LLL + CM group compared to the hypothyroidism group (P < 0.05). Conclusion: The results indicated that using the LLL + CM may improve fracture regeneration and it may hasten bone healing in the hypothyroid rat.

Background: Spinal cord injury is a progressive process that initially causes abnormal nerve connections. Following spinal cord injury, the spinal cord is impaired after which cell death and apoptosis occurs. Primary damage happens in the spinal cord due to the demyelization of the large axons. Cell therapy is among the new strategies that have been considered for the treatment of neural injuries in recent years. Aim: In this narrative review article, we discuss &quot;Cell Therapy&quot; as a new and safe strategy for the treatment of spinal cord injury. we are going to explain the epidemiological and pathophysiological aspects of spinal cord injuries (SCI) as well as SCI experimental and clinical stem cell strategies. Conclusion: There are several promising advancements and findings in the field of stem cell biology and cell reprogramming, with the aim of treating patients with SCI via stem cell therapy. We reviewed critical issues for clinical translation and we also provided a com...

Background: Oxidative stress and neuroinflammation have found to be implicated in several neurodegenerative disorders (ND). Neuroprotection against oxidative agents has been proposed as a therapy on the basis that it might prevent neuroinflammation. Curcumin is an anti-oxidant with anti-inflammatory properties which has been proposed to be used as a therapeutic agent in ND. Aim: In this study, we examined the neuroprotective effect of curcumin on neural stem cells (NSCs) exposed to H 2 O 2 as an oxidative injury model. Methods: After culturing NSCs, they were co-treated with curcumin and H 2 O 2 , after which their effects were tested on cell viability using MTT assay. Results: Our results indicated that the high concentration of H2O2 significantly promoted cell death. Specifically, after using 250 µM of H2O2, the mortality increased dramatically in comparison with the control groups. On the other hand, the presence of curcumin encouraged cell survival of NSCs treated with H2O2. Con...

Background: Extensive research on bone tissue engineering as a novel therapeutic approach to design and fabricate suitable scaffolds is in progress to overcome the limitations of conventional bone repair techniques. In recent years, tissue engineering and remedial medicine have come up with the strategy of designing, fabricating, and optimizing synthetic and natural scaffolds containing cells and growth factors to facilitate the direct and indirect mechanisms of bone tissue repair in the body. Based on many studies, cellular source, cell medium condition, and biological scaffolds are critical factors in bone defect repair in the field of tissue engineering. Aim: In this review, we focus on the combination of mesenchymal cells derived from the human adipose tissue, stem cell-to-bone differentiation medium, and biocompatible polyvinyl alcohol-graphene oxide scaffolds in bone lesion repair to gain a better understanding of each factor. This would, in turn, help us design and develop op...

Background: The mammal&#39;s inner ear is responsible for hearing and balance. To perform these tasks, it requires the vestibular and cochlear system. Sensor neural hearing loss (SNHL) is the most common type of hearing loss resulting in degeneration of internal sensory hair cell, where cochlear nerve in cochlear stem cell and gene-based strategies provide the opportunity for replacement for these cells. Aim: In this review, we evaluated the efficiency of stem cell therapy in inner ear. Methods: In this study we examined different articles in different databases such as Google Scholar, PubMed, and Elsevier. Results: The stem cells have offered desired results in the delivery of gene and tissue engineering programs. Evidence suggests that stem cells are considered as a promising tool in medical applications thanks to their high plasticity and trophic characteristics. Conclusion: In this review, Stem cell transplantation is widely used in clinical practice, and the source is highly de...

Methamphetamine (METH) abuse is accompanied by oxidative stress, METH-induced neurotoxicity, and apoptosis. Oxidative stress has devastating effects on the structure of proteins and cells. Autophagy is an evolutionarily conserved intracellular regulated mechanism for orderly degradation of dysfunctional proteins or removing damaged organelles. The precise role of autophagy in oxidative stress-induced apoptosis of dopaminergic neuronal cells caused by METH has not clarified completely. In this study, we sought to evaluate the effects of METH abuse on autophagy in the prefrontal cortex of postmortem users, mainly focusing on the ATG5 and LC3 during neuroinflammation. Postmortem molecular and histological examination was done for two groups containing 12 non-addicted and 14 METH addicted cases. ATG5 and LC3 expression were analyzed by real-time PCR and immunohistochemistry (IHC) methods. Histopathological analysis was performed by stereological cell counting of neuronal cells using Hematoxylin and Eosin (H & E) staining technique. In order to detect DNA damage in the prefrontal lobe, Tunnel staining was performed. Real-time PCR and IHC assay showed overexpression of ATG5 and LC3 protein in the prefrontal cortex of Meth users. The cell death and neuronal degeneration were increased significantly based on Tunel assay and the stereological analysis in the Prefrontal cortex. Chronic METH exposure probably induces ATG5 and LC3 overexpression and neuronal cell death in the Prefrontal cortex of the postmortem cases.

Amyloid b (Ab) fibrils and amorphous aggregates are found in the brain of patients with Alzheimer's disease (AD), and are implicated in the etiology of AD. The metal imbalance is also among leading causes of AD, owing to the fact that Ab aggregation takes place in the synaptic cleft where Ab, Cu(II) and Fe(III) are found in abnormally high concentrations. Ab40 and Ab42 are the main components of plaques found in afflicted brains. Coordination of Cu(II) and Fe(III) ions to Ab peptides have been linked to Ab aggregation and production of reactive oxygen species, two key events in the development of AD pathology. Metal chelation was proposed as a therapy for AD on the basis that it might prevent Ab aggregation. In this work, we first examined the formation of Ab40 and Ab42 aggregates in the presence of metal ions, i.e. Fe(III) and Cu(II), which were detected by fluorescence spectroscopy and atomic force microscopy. Second, we studied the ability of the two chelators, ethylenediaminetetraacetic acid and 5-chloro-7-iodo-8-hydroxyquinoline (clioquinol), to investigate their effect on the availability of these metal ions to interact with Ab and thereby their effect on Ab accumulation. Our findings show that Fe(III), but not Cu(II), promote aggregation of both Ab40 and Ab42. We also found that only clioquinol decreased significantly iron ion-induced aggregation of Ab42. The presence of ions and/or chelators also affected the morphology of Ab aggregates. Keywords b amyloid peptide Á Cu(II) ion Á Fe(III) ion Á Clioquinol Á EDTA

Introduction: Many studies have shown the positive effect of laser radiation and application of the mesenchymal stem cells (MSCs) and their secretion in stimulating bone regeneration. The aim of this study was determining effects of MSC conditioned media (CM) and low-level laser (LLL) on healing bone defects in the hypothyroid male rat. Methods: We assigned 30 male Wistar rats randomly to 3 groups: control, hypothyroidism, CM+LLL. Four weeks after surgery, the right tibia was removed. Biomechanical examination and histological examinations were performed immediately. Results: Our results showed significant increase in bending stiffness (116.09±18.49), maximum force (65.41±8.16), stress high load (23.30±7.14), energy absorption (34.57±4.10), trabecular bone volume (1.34±0.38) and the number of osteocyte, osteoblast, and osteoclast (12.77±0.54, 6.19±0.80, 1.12±0.16 respectively) in osteotomy site in the LLL+CM group compared to the hypothyroidism group (P&lt;0.05). Conclusion: The res...

Introduction: Bone marrow stromal stem cells (BMSCs), a type of adult stem cells, secrete bioactive molecules such as trophic factors, growth factors, chemokine and cytokines that may be effective against oxidative stress in neurodegenerative diseases. In this study, we examined the protective effect of BMSCs conditioned media (CM) and photobiomodulation therapy (PBMT) on PC12 cells exposed to H2O2 as an oxidative injury model. Methods: BMSCs were cultured and confirmed by flow cytometry analysis and underwent osteogenic and adipogenic differentiation. Then, PC12-H2O2 cells were co-treated with BMSCs-CM and PBMT. The effect of BMSCs-CM and PBMT (He-Ne laser, 632.8nm, 3mW, 1.2J/ cm2 , 378s) on Bax/Bcl2 expression, cell viability, was assessed by real-time PCR and MTT assay. The length of the Neurite and cell body areas were assessed by Cell A software. Results: Flowcytometry analysis, as well as osteogenic and adipogenic staining, confirmed the BMSCs. The length of the Neurite was th...

Introduction: Parkinson’s disease (PD) is one of the most common neurodegenerative disorders. The neuroinflammation in the brain of PD patients is one of the critical processes in the immune pathogenesis of PD leading to the neural loss in the substantia nigra. Due to the anti-inflammatory effects of curcumin (CU) and low-level laser therapy (LLLT), we examined the protective effect of CU and LLLT on PC12 cells treated with 6-hydroxydopamine (6-OHDA) as a Parkinson model. Methods: PC12 cells were pretreated using various concentrations of 6-OHDA for 24 hours to induce oxidative and cellular damages. PC12-6-OHDA cells were co-treated with CU and LLLT. The effects of CU and LLLT on Bax/Bcl2 and LC3/ATG10 expression were analyzed by real-time PCR and cell viability was assessed by MTT assay. Cell A Software was used to calculate the length of the Neurite and cell body areas. Results: The results of this study show that the combination of CU dose-dependently and LLLT has a significant n...

STING-Type I interferon (IFN) signaling in myeloid cells plays a critical role in effective antitumor immune responses, but STING agonist as monotherapy has shown limited efficacy in clinical trials. The mechanisms that downregulate STING signaling are not fully understood. Here, we report that Protein phosphatase 2A (PP2A) with its specific B regulatory subunit STRN4 negatively regulated STING-Type I IFN in macrophages. Mice with macrophages PP2A deficiency exhibited reduced tumor progression. The tumor microenvironment showed decreased immunosuppressive and increased IFN-activated macrophages and CD8+ T cells. Mechanistically, we demonstrated that hippo kinase MST1/2 was required for STING activation. STING agonist induced dissociation of PP2A from MST1/2 in normal macrophages, but not in tumor conditioned macrophages. Furthermore, our data showed that STRN4 mediated PP2A binding to and dephosphorylation of hippo kinase MST1/2, resulting in stabilization of YAP/TAZ to antagonize STING activation. In human GBM patients, YAP/TAZ was highly expressed in tumor-associated macrophages but not in non-tumor macrophages. We also demonstrated that PP2A/STRN4 deficiency in macrophages reduced YAP/TAZ expression and sensitized tumor conditioned macrophages to STING stimulation. In summary, we demonstrated that PP2A/STRN4-YAP/TAZ is a previously unappreciated mechanism that mediate immunosuppression in tumorassociated macrophages and targeting PP2A/STRN4-YAP/TAZ axis can sensitize tumors to immunotherapy.

Introduction: Diabetes poses a global health challenge, giving rise to various complications, including diabetic foot ulcers (DFUs). DFUs, marked by ischemic ulcers susceptible to infection and amputation, underscore the urgency for innovative treatments. This study investigated the impact of photobiomodulation therapy (PBT) and autologous platelet gel (APG) on DFUs recovery. Methods: We systematically searched Web of Science, EMBASE, MEDLINE, Cochrane Library, Scopus, and Google Scholar (2015-2023) by using pertinent terms like &quot;photobiomodulation therapy,&quot; &quot;low level light therapy,&quot; and &quot;platelet gel.&quot; After meticulous data extraction and review, 57 articles were chosen and categorized. Among these, three randomized controlled trials involving 186 participants were selected for APG analysis. Results: Findings demonstrate that APG application carries minimal risk and offers promising improvements in healing time, grade, pain reduction, and granulation ...

Methamphetamine (METH) can potentially disrupt neurotransmitters activities in the central nervous system (CNS) and cause neurotoxicity through various pathways. These pathways include increased production of reactive nitrogen and oxygen species, hypothermia, and induction of mitochondrial apoptosis. In this study, we investigated the long-term effects of METH addiction on the structural changes in the amygdala of postmortem human brains and the involvement of the brain-cAMP response element-binding protein/brain-derived neurotrophic factor (CREB/BDNF) and Akt-1/GSK3 signaling pathways. We examined ten male postmortem brains, comparing control subjects with chronic METH users, using immunohistochemistry, real-time polymerase chain reaction (to measure levels of CREB, BDNF, Akt-1, GSK3, and tumor necrosis factor-α [TNF-α]), Tunnel assay, stereology, and assays for reactive oxygen species (ROS), glutathione disulfide (GSSG), and glutathione peroxidase (GPX). The findings revealed that METH significantly reduced the expression of BDNF, CREB, Akt-1, and GPX while increasing the levels of GSSG, ROS, RIPK3, GSK3, and TNF-α. Furthermore, METH-induced inflammation and neurodegeneration in the amygdala, with ROS production mediated by the CREB/BDNF and Akt-1/GSK3 signaling pathways.

Background and Aim: Due to the increased incidence of overweight and obesity, its associated co-morbidities have also been reported to be escalating. Resting tachycardia, increased rate pressure product (RPP) and decreased heart rate variability (HRV) contribute to cardiovascular (CV) risks. Therefore, in the present study HRV indices and CV risks in overweight and obese subjects have been assessed. Methods: Body mass index (BMI), waist circumference, waist-to-hip ratio, waist-to-height ratio (WHtR) and basal CV parameters were assessed in control (N = 50), overweight (N = 50) and obese (N = 50) group subjects. Spectral analysis of HRV was performed in all these groups using Biopac system. Results: The basal CV parameters were significantly increased in overweight and obese subjects compared to controls. Low-frequency to high-frequency ratio (LF-HF ratio), marker of sympathovagal imbalance (SVI) was increased in overweight and obese subjects compared to controls. Total power (TP) and high frequency component expressed as normalized unit (Hfnu) which reflects the overall vagal drive to heart, was significantly decreased and low frequency component expressed as normalized unit (Lfnu) which reflects the sympathetic cardiac modulation, was significantly increased, in overweight and obese subjects compared to controls. These CV risks were predominately more in obese compared to overweight subjects. Conclusion: Increased resting heart rate, RPP and decreased HRV due to sympathetic activation and vagal withdrawal observed in overweight and obese subjects might contribute to the increased CV risk in these high risk populations.

Sympathovagal imbalance in obesity: Cardiovascular perspectives sympathovagal imbalance (SVI) due to inequality between the sympathetic and parasympathetic activities has emerged as the key pathophysiological mechanism to explain the role of autonomic neuro-physiological mechanisms in various clinical disorders. [15-24] In this article, we have reviewed the concept, cause, mechanism and effects of SVI in obesity and its possible link to CV disorders. Also, we have suggested the possible methods for preventing CV risks in overweight and obese subjects by restoring sympathovagal homeostasis. SYMPATHOVAGAL IMBALANCE: CONCEPT AND IMPORTANCE Autonomic responses are the emotional responses of the body to the environment that occurs without the conscious effort of an individual. These responses are executed through the autonomic part of the nervous system, known as ANS. [25] ANS through its two major subdivisions: The sympathetic and the parasympathetic systems innervate all visceral organs to control the major functions of the body, such as circulation, respiration, digestion, excretion, reproduction, immunity, and metabolism. Broadly, the sympathetic system is involved in energy mobilization and utilization, and the parasympathetic system in energy restoration and storage. [25] In a healthy person, the body tries to maintain a balance between the