Pyknotic Cells Research Articles

Neuroprotective effect of Orostachys spinose dry extract in cholinergic insufficiency

Background. Orostachys spinosa (L.) Sweet. – a perennial plant of a wide habitat and contains various metabolites (amino acids, flavonoids, polysaccharides, etc.). Extracts from the aerial part of the plant are used in traditional medicine as an anticonvulsant and sedative.The aim of the work. To study the neuroprotective effect of O. spinosa in cholinergic deficiency.Materials and methods. The studies were carried out on 52 Wistar rats. The animals were administered scopolamine (1 mg/kg) daily for 21 days, followed by O. spinosa dry extract per os at a dose of 100 mg/kg for 14 days. On the day 32, the animals developed a conditioned passive avoidance reflex (CPAR), the integrity of which was checked after 1, 24 and 72 hours; on the day 35 they were tested in an “open field”. On the day 36, biochemical and histological studies of the brain were carried out.Results. It has been established that O. spinosa, against the background of scopolamine intoxication, reduces the anxiety of animals, stimulates exploratory activity in the open field test, improves the production and preservation of the CPAR, and also reduces the number of functionally inactive neurons (pyknotic and shadow cells) in the cerebral cortex. The extract reduces the lactate/pyruvate ratio by 47 %, intensifies the activity of mitochondrial complexes I and II by 54–64 %, and increases the concentration of adenosine triphosphate by 1.6 times compared to the control. O. spinosa exhibits antioxidant properties by reducing malondialdehyde and increasing the activity of catalase, glutathione peroxidase and glutathione reductase in the brain.Conclusion. O. spinosa dry extract has a neuroprotective effect in cholinergic deficiency. The studied extract exhibits antioxidant properties and stimulates energy processes in the brain

Impact of Mild Gestational Diabetes Mellitus on Maternal and Fetal Liver Histopathological Alterations

Background: Gestational diabetes mellitus (GDM) is one of the most common pregnancy complications that can affect the organ systems of the body in both the mother and fetus. This study aimed to determine the impact of mild GDM on maternal and fetal liver histopathological alterations. Materials and Methods: In this experimental study, 20 pregnant Wistar rats were randomly allocated in control and diabetic groups. Mild hyperglycemia was induced by intraperitoneal injection of streptozotocin (40 mg/kg body weight) on the 5th day of gestation. The control group received an equal volume of citrate buffer. The diabetic state was confirmed by a blood glucose level of 120–300 mg/dL. Maternal and fetal liver samples were obtained on day 19 of gestation and stained with hematoxylin and eosin for histopathological investigation. Results: Liver sections of diabetic dams exhibited edematous hepatocytes and scattered pyknotic and necrotic cells with dilated sinusoids and congested central veins. The portal tracts showed the proliferation of bile ducts with mild chronic inflammatory cells infiltrating together with fibrosis beyond the limited plate which extends to the central vein (porto-central fibrosis). Liver sections of their fetuses revealed edematous hepatocytes with increased necrotic cells, with pyknotic nuclei, dilatation of the hepatic sinusoids, and their central veins. There was also a relative increase in megakaryocytes, which promoted fibrosis and distorted vascular beds of the hepatic tissue. The portal tracts also showed bile duct proliferation. Conclusion: This study highlighted the adverse effects of uncontrolled mild GDM on liver structure in rat dams and their fetuses.

Morphological evaluation of adult domestic cat testicular biopsy after vitrification.

Testicular biopsies (9 mm3) from domestic cats (n = 10) submitted to orchiectomy were submitted to equilibrium vitrification in the presence of ethylene glycol (EG) alone or combined with dimethylsulfoxide (DMSO) as intracellular cryoprotectants, and sucrose or trehalose as extracellular cryoprotectants. The samples were vitrified with 40% EG or 20% EG + 20% DMSO, plus 0.1 M or 0.5 M of sucrose or trehalose. The study was divided into Step 1 and Step 2. In Step 1, intratubular cells (spermatogonia, spermatids, spermatocytes, and Sertoli cells) were quantified and classified as intact or degenerated (pyknotic and/or vacuolated cells). Cryodamage of seminiferous cords was determined by spermatogonia and Sertoli cell scoring of nuclei alterations, tubular basement membrane detachment, epithelium shrinkage, and tubular measures (total area, epithelium area, larger and smaller diameter, and height of the epithelium). In Step 2, Hoechst 33342 stain and propidium iodide (PI) fluorescent stain were used to assess the cell viability of the four best experimental groups in Step 1. The effect of treatments on all analyses was accessed using analysis of variance (ANOVA), and Fisher's post hoc test at P < 0.05 significance was considered. In Step 1, the mean percentage of spermatogonia and Sertoli cells morphological integrity did not show a difference when using both sugars at different concentrations, but their morphology was more affected when DMSO was used. EG use associated with 0.1 M of sucrose or trehalose positively affected spermatocyte and spermatid morphology, respectively. The larger diameter and epithelium height of seminiferous tubules were increased using DMSO plus 0.5 M sucrose and DMSO plus 0.1 M trehalose. The changes in spermatogonial/Sertoli nucleoli visualization were best scored in the EG groups, while the nuclei condensation was lower with sucrose. The basement membrane was satisfactorily preserved with 0.1 M sucrose. In Step 2, the percentage of cell viability was higher when EG plus 0.1 M sucrose was used. Therefore, DMSO's negative effect on the vitrification of testicular biopsies of adult domestic cats was evident. The EG plus 0.1 M of sucrose or trehalose associations are the most suitable CPAs to preserve the testicular histology structure of adult domestic cats in vitrification.

Ultrastructural and immunohistochemical evaluation of hyperplastic soft tissues surrounding dental implants in fibular jaws

In reconstructive surgery, complications post-fibula free flap (FFF) reconstruction, notably peri-implant hyperplasia, are significant yet understudied. This study analyzed peri-implant hyperplastic tissue surrounding FFF, alongside peri-implantitis and foreign body granulation (FBG) tissues from patients treated at the Department of Oral and Maxillofacial Surgery, Seoul National University Dental Hospital. Using light microscopy, pseudoepitheliomatous hyperplasia, anucleate and pyknotic prickle cells, and excessive collagen deposition were observed in FFF hyperplastic tissue. Ultrastructural analyses revealed abnormal structures, including hemidesmosome dilation, bacterial invasion, and endoplasmic reticulum (ER) swelling. In immunohistochemical analysis, unfolded protein-response markers ATF6, PERK, XBP1, inflammatory marker NFκB, necroptosis marker MLKL, apoptosis marker GADD153, autophagy marker LC3, epithelial–mesenchymal transition, and angiogenesis markers were expressed variably in hyperplastic tissue surrounding FFF implants, peri-implantitis, and FBG tissues. NFκB expression was higher in peri-implantitis and FBG tissues compared to hyperplastic tissue surrounding FFF implants. PERK expression exceeded XBP1 significantly in FFF hyperplastic tissue, while expression levels of PERK, XBP1, and ATF6 were not significantly different in peri-implantitis and FBG tissues. These findings provide valuable insights into the interconnected roles of ER stress, necroptosis, apoptosis, and angiogenesis in the pathogenesis of oral pathologies, offering a foundation for innovative strategies in dental implant rehabilitation management and prevention.

Evaluation of Cytotoxic and Genotoxic Effects in Buccal Mucosal Cells in Non-Smokers and Users of Traditional Combustible Tobacco Products and Non-Combustible Alternatives.

The aim of this cross-sectional observational study was to investigate cytogenetic damage to the buccal mucosa in non-smokers and consumers of traditional combustible tobacco products and non-combustible alternatives. A total of 160 participants were divided into four groups according to the type of product used, including non-smokers, users of conventional combustible tobacco (cigarettes), heated tobacco, and electronic, tobacco-free vapor products (e-cigarettes). Buccal mucosa samples were analyzed using the micronucleus cytome assay to assess cytotoxic and genotoxic damage. E-cigarette users showed significantly higher values for all tested parameters in the micronucleus test compared to non-smokers (p < 0.05). Similarly, users of tobacco heating products showed an increase in all parameters (p < 0.05), with the exception of the number of cells with micronuclei. Conventional cigarette smokers showed a notable increase in the number of binucleated cells and cells with karyorrhexis and karyolysis (p ≤ 0.05). When assessing the differences between users of traditional combustible tobacco products and non-combustible alternatives, these did not appear to be significant, except for e-cigarette users, who had significantly more cells with condensed chromatin (p ≤ 0.001), while users of tobacco heating products had more pyknotic cells (p ≤ 0.001). The results of this study underscore the heightened occurrence of cytotoxic and genotoxic damage in users of both conventional combustible tobacco products and non-combustible alternatives compared to non-smokers, emphasizing the detrimental impact of these products on the oral mucosa.

Vanadium administration ameliorates cortical structural and functional changes in juvenile hydrocephalic mice.

Vanadium is a prevalent neurotoxic transition metal with therapeutic potentials in some neurological conditions. Hydrocephalus poses a major clinical burden in neurological practice in Africa. Its primary treatment (shunting) has complications, including infection and blockage; alternative drug-based therapies are therefore necessary. This study investigates the function and cytoarchitecture of motor and cerebellar cortices in juvenile hydrocephalic mice following treatment with varying doses of vanadium. Fifty juvenile mice were allocated into five groups (n=10 each): controls, hydrocephalus-only, low- (0.15mg/kg), moderate- (0.3mg/kg), and high- (3.0mg/kg) dose vanadium groups. Hydrocephalus was induced by the intracisternal injection of kaolin and sodium metavanadate administered by intraperitoneal injection 72hourly for 28 days. Neurobehavioral tests: open field, hanging wire, and pole tests, were carried out to assess locomotion, muscular strength, and motor coordination, respectively. The cerebral motor and the cerebellar cortices were processed for cresyl violet staining and immunohistochemistry for neurons (NeuN) and astrocytes (glial fibrillary acidic protein). Hydrocephalic mice exhibited body weight loss and behavioral deficits. Horizontal and vertical movements and latency to fall from hanging wire were significantly reduced, while latency to turn and descend the pole were prolonged in hydrocephalic mice, suggesting impaired motor ability; this was improved in vanadium-treated mice. Increased neuronal count, pyknotic cells, neurodegeneration and reactive astrogliosis were observed in the hydrocephalic mice. These were mostly mitigated in the vanadium-treated mice, except in the high-dose group where astrogliosis persisted. These results demonstrate a neuroprotective potential of vanadium administration in hydrocephalus. The molecular basis of these effects needs further exploration.

Pathological effects of pregabalin toxicity in rats

Abstract Background: Pregabalin (PGB) is one kind of gabapentinoid. The main mechanism of action is binding at the alpha-2-delta site, which inhibits calcium influx in response to depolarization at nerve terminals and, in turn, suppresses the release of glutamate, noradrenaline, and substance P. Objectives: This study aimed to study the pathological effects of PGB toxicity on brain and liver of rats. Materials and Methods: We chose 20 mature albino rats, both sexes, averaging 220 g in weight; these were divided into two groups (10 rats per group): the toxic group and the control group. Tablets of Lyrica (Pfizer) may be purchased over the counter. The 300 mg of PGB in each tablet was dissolved in 3 mL of 0.9% normal saline. The dosage was determined using the maximum lethal oral dose in rats (5000 mg/kg) (Pfizer, 2017). Based on the rats’ weights, a toxic dosage of 1000 mg of PGB was determined and reconstituted in normal saline (0.9% in 3 mL). Each animal in the acute toxicity group received a single dose of the produced medication orally. After 24 h, all of the animals in both groups were euthanized. The brain and liver were quickly dissected and removed, washed in saline solution, and then processed for histopathological study. Results: Focal regions of hemorrhage and congestion were seen in H&amp;E-stained sections from the acute toxicity group, and most pyramidal cells were degraded, pyknotic, and exhibited karyolysis. Cerebellar cortical layers were preserved; however, Purkinje cells were destroyed in the acute toxicity group, which also exhibited an increase in pyknotic cells, hemorrhage, vascular congestion, and localized loss of tissue. Hemorrhages, congestion of portal region blood vessels, and central veins and hepatic sinusoids were some of the most notable pathological abnormalities seen in the livers of those using PGB. Hepatocytes show nuclear pyknosis and a homogeneously acidophilic cytoplasm as a result of severe degenerative alterations, such as vacuolar degeneration and severe necrotic changes. Conclusion: PGB can cause pathological lesions in the brain and liver at a single toxic dose.

Amelioration of nonylphenol-induced anxiety/depression-like behaviors in male rats using green tea and Zn-Se tea interventions.

This study aimed to investigate the effects of exposure to nonylphenol (NP) on anxiety/depression-like behaviors in rats and alleviation of those effects via green tea and zinc selenium (Zn-Se) tea interventions. Totally, 40 male specific-pathogen free (SPF) Sprague-Dawley (SD) male rats were randomly divided into four groups (n=10 rats per group): control group (5 ml/kg corn oil), NP group (40 mg/kg NP), NP + GT group (40 mg/kg NP + 1 g/kg/day green tea), and NP + Zn-Se tea group (40 mg/kg NP + 1 g/kg/day ZST). All dose-based groups received oral gavage of either corn oil or drugs over a 6-month period: NP at a dosage of 40 mg/kg/day was administered to rats for the initial 3 months, followed by a combination of NP with green tea and NP with Zn-Se tea for the subsequent 3 months. Tea intervention resulted in weight loss in rats. The hippocampal tissue NP level in the tea group was slightly lower than that in the NP group. Following tea intervention, compared with the NP group, the residence time in the light-dark box test was shortened PGT=0.048, P<0.001), and the number of entries into the closed arm in the elevated plus maze test in the tea-treated group was significantly reduced. In addition, the immobility time in the central square in the open field test decreased. The sucrose preference index score in the sucrose preference test increased, and the immobility time in the forced swimming test was reduced (PGT = 0.049, PZST<0.001). The effects of Zn-S e tea were superior to green tea. The damage to the hippocampal tissues in the group treated with tea was less than that in the NP group. The cellular arrangement was tighter with degeneration, deepstaining, and pyknotic nerve cells were visible. The nuclei in the NP group were atrophied, and the cells were sparsely arranged. Compared with the control group, serum brain-derived neurotrophic factor (BDNF) level was lower in the NP group. The serum corticosterone level in the NP group was elevated. Compared with the NP group, serum corticosterone level was reduced in the NP + Zn-Se tea group. Chronic NP exposure induced anxiety/depression-like behaviors in rats. Green tea effectively reduced the damage to the hippocampus and prefrontal cortex induced by NP. The effects of Zn-Se tea were slightly more noticeable than those of conventional green tea. 1) Chronic NP exposure induced anxiety/depression-like behaviors in rats.2) Zn-Se tea reduced the damage of hippocampal and prefrontal cortex induced by NP.3) NP-induced depression accompanied by the changes of BDNF, CORT and neuropathology.

Exploratory Study on Micronuclei and Metanuclear Abnormalities in Exfoliated Buccal Cells of COVID-19 Suspected Patients.

SARS-CoV-2 virus causes COVID-19 by infecting nasal and oral cavities primarily by attaching its spike proteins to ACE 2 receptors expressed in epithelial cells. This study was done to evaluate the micronucleated cell count, metanuclear abnormalities, and genotoxic factor in exfoliated buccal mucosal cell among the COVID-19 suspected patients. This cross-sectional study was conducted at AIIMS, Mangalagiri, between August and October 2022. One hundred COVID-19 suspected patients were recruited for this study after obtaining informed and written consent; buccal smear was obtained and stained for papanicolaou test (PAP). The PAP-stained slides were analyzed for micronuclei (MN), pyknotic, karyolytic, and karyorrhexic cell count, respectively. Based on their reverse transcription-polymerase chain reaction (RT-PCR) report, the patients were grouped into COVID-19 positive and negative groups. The genotoxicity factor was calculated using the micronucleated cell count from both the groups using mean and standard deviation. The MN, micronucleated cell, pyknotic, karyolitic, and karyorrhexic cell count in COVID-19 positive patients were 24.12, 15.24, 3.08, 2.88 and 4.40, respectively, than COVID-19 negative patients 5.69, 8.17, 1.08, 1.00 and 2.43, respectively. The genotoxicity factor for SARS-CoV-2 was 2.68 which is a positive genotoxic effect on buccal mucosal cells. SARS-CoV-2 increases the expression of micronucleated cells, pyknotic cells, karyolytic cells, and karyorhexic cells and concludes SARS-CoV-2 is having cytogenotoxic effect on the buccal mucosal cells. This can be used as a reliable marker in identifying the early carcinogenic effects of virus causing COVID-19.

Palmitoylethanolamide Modulates Gait By Targeting Purkinje Cells in the Brain of Sickle Mice

Chronic pain is a major comorbidity of sickle cell disease (SCD). Transgenic humanized (BERK) sickle mice recapitulate many clinical features of SCD, including chronic pain. Motor impairments concomitant with increased pyknotic cerebellar Purkinje cells occur in BERK sickle mice. Neurological, neuropathic, and immunological factors, including Purkinje cell damage and chronic inflammation, may contribute to peripheral and central mechanisms that drive gait dysfunction. Pathological changes in Purkinje cells of sickle mice include a significantly greater number of pyknotic cells with smudged nuclei, condensed chromatin, and lack of well-formed nucleoli, &amp; may contribute to alterations in gait as Purkinje cells regulate sensory-motor functions. Subjects with SCD often use cannabinoids for pain relief, but the intoxicating effects and social stigma associated with their use represent barriers to utilizing this treatment. Palmitoylethanolamide (PEA) is a non-intoxicating endocannabinoid-like lipid mediator naturally produced throughout the body that may act via indirect cannabinoid receptor activation. In clinical studies associated with movement and pain, including chronic arthritic and multiple sclerosis, PEA has demonstrated a reduction of motor dysfunction and pain. Therefore, we examined the effect of PEA on hyperalgesia and gait in humanized HbSS-BERK sickle (HbSS) mice. We utilized ~6-month-old female, HbSS mice, expressing &amp;gt;99% human α- and ßS- sickle hemoglobin and complete knockout of murine α- and β-globins. Mice were treated with PEA (ip, 20 mg/kg/d) or vehicle (7.5% DMSO, 7.5% Tween 20, in sterile saline) for 2 weeks (2-wks). Gait measurements were gathered for each mouse at baseline (BL) and 2-wks post treatment during normal walking in MouseWalker's transparent corridor with a floor panel mounted with LED lights to produce a detectable touch sensor. Physical contact of paw pads with the surface during natural walking disrupts the light path, causing frustrated total internal reflection detected by a high-speed camera and analyzed using artificial intelligence-based algorithms for gait parameters. Mechanical hyperalgesia was analyzed as paw withdrawal frequency (PWF) in response to 10 applications of 1.0 g von Frey monofilaments. Complete blood counts and brain histopathology on hematoxylin- and eosin-stained sections were evaluated after 2-wks post-treatment. We observed that PEA ameliorates features of dysfunctional gait in HbSS mice. PEA-treated mice show increased limb swing speed (~30%, P&amp;lt;0.01) and shortened swing duration (20%, P&amp;lt;0.05) without affecting walking speed (P &amp;gt;0.05) Vs. vehicle-treated mice. Also, PEA significantly reduced body instability (~75%, P&amp;lt;0.05) and improved stance duration (~65%, P&amp;lt;0.05) Vs. BL. This suggests improved limb coordination and reduced sensitivity to mechanical forces during walking. Complementary to gait changes, PEA significantly decreased mechanical hyperalgesia, indicated by lower PWF, 1-hour following initial treatment and following 2-wks post-treatment (~55%, P&amp;lt; 0.001 and ~65%, P&amp;lt; 0.001, respectively) Vs. BL. PEA decreased the number of circulating white blood cells (P&amp;lt; 0.05), with the greatest reduction in circulating lymphocytes (P&amp;lt; 0.1). PEA had no adverse effects on organ weight Vs. vehicle treatment. PEA-treated mice showed a significant reduction in pyknotic cerebellar Purkinje cells (~23.9% p&amp;lt;.006) in the brain Vs. vehicle. Thus, Purkinje cell pathology may contribute to impaired gait, and PEA may improve motor coordination by reducing Purkinje cell damage. We provide the first evidence that PEA administration in a humanized sickle mouse model improves features of gait, restores Purkinje cell morphology, and reduces inflammation. Our data demonstrate that PEA may have a disease-modifying effect and restoration of sensory-motor function in SCD. Impairment in gait may also be due to avascular necrosis. Therefore gait measurements may provide a non-invasive analysis of movement associated pathology and pain as well as effectiveness of targeted interventions.

The Effect of Moderate Intensity Interval Training (MIIT) on Short-Term Memory Function, the Ratio of Neocortical Neurons and Glial Cells, and the Number of Hippocampal Pyknotic Granule Cells in Rats on a High-Calorie Diet

Consumption of a high-calorie diet correlates with increased metabolic disturbances that lead to various organ disorders, including neurodegenerative disease. Women are more susceptible to metabolic disorders due to a high-calorie diet, so they have higher risk factors for neuroinflammation. This study was conducted to explain the effect of Moderate Intensity Interval Training (MIIT) on short-term memory, neocortex glia neuron ratio, and hippocampal pyknotic granule cells in female Wistar rats (Rattus norvegicus) with a high-calorie diet. The Wistar rats used were two months old. The study was conducted for four weeks, preceded by the acclimatization of experimental animals. MIIT intervention in the form of swimming is done every 5 minutes with a rest period of 2.5 minutes with two repetitions. Measurement of short-term memory using Y-maze instrument. Results: Before treatment, the highest average body weight was in groups C, B, and A (p=0.006). After treatment, the highest average body weight was found in groups B, C, and A (p=0.569). The test results of short-term memory measurement using the alternation indicator showed no significant difference between groups in the pre-alternation test (p=0.481). There was a significant difference between groups for the neuron-glia ratio (p=0.370) and the hippocampus of the pyknosis granule cells (p=0.078). In conclusion, there is a significant difference between groups A, B, and C towards the MIIT intervention.

Azilsartan ameliorates aluminium chloride induced Alzheimer’s disease like pathology

Abstract Alzheimer’s disease (AD) is a neurodegenerative disease manifested with accumulation of neurotoxic proteins like beta-amyloid (Aβ) and hyperphosphorylated tau. Administration of angiotensin receptor blockers (ARBs) such as Telmisartan has demonstrated to generate significant memory improvement in AD. Azilsartan is an ARB with better bioavailability than Telmisartan. Hence, the present work evaluates the efficacy of Azilsartan against aluminium chloride (AlCl3) induced AD. In the work, albino rats were divided into five groups (n=6). Group I served as control and received saline (10 ml/kg). Group-II was treated with AlCl3 (100 mg/kg) for 42 days; Group-III and IV received Azilsartan (5 mg/kg) and Telmisartan (10 mg/kg) with AlCl3 daily for 42 days. Y-maze, elevated plus maze and radial arm maze were used to evaluate memory functions. This was followed by biochemical and histological studies, along-with determination of Aβ content and anti-oxidant status. AlCl3 was found to significantly (p &lt;0.05) reduce cognition and increased concentration of Aβ in a hippocampus with elevated lipid peroxidation levels. It also significantly (p&lt;0.05) decreased superoxide dismutase and increased malondialdehyde content. However, brain histology showed presence of neurofibrillary tangles, neuronal dead cells, and pyknotic cells compared to normal group. Still, Azilsartan and Telmisartan significantly (p&lt;0.05) reversed cognitive dysfunction, improved antioxidant status and decreased Aβ production. Thus we conclude that Azilsartan protects AlCl3 induced AD-like pathology but, to a degree less than Telmisartan.

Saffron stigma extract and crocin play an important neuroprotective role in therapeutic measures against benzo[a]pyrene-induced behavioral alterations in zebrafish

Saffron is a well-known expensive spice, which has many pharmacological properties against a variety of ailments. Saffron stigma and leaf contain apocarotenoids and bioactive phytochemicals having therapeutic potential against human disorders. Polycyclic aromatic hydrocarbons (PAHs) are one of the most common toxins in today’s aquatic environment. Benzo[a]pyrene (B[a]P), a high molecular weight PAHs prototype, and reported as a potent neurotoxicant, which is profoundly contaminating the environment. The present study investigated the therapeutic efficacy of Saffron stigma extracts and crocin, on B[a]P-induced behavioral changes, altered antioxidant activities, and neurodegeneration in zebrafish. The behavioral responses monitored through the light-dark preference test and novel tank diving test suggested that B[a]P treated zebrafish group showed alteration in anxiolytic-like behavior. Animals exhibited their native behavior when treated alone with Saffron Stigma Extract (SSE) and crocin, an apocarotenoid which also reduced the altered behavior induced by B[a]P. The SSE and crocin stimulated the antioxidant activities with an accumulation of reduced glutathione and catalase enzymes, indicating a protective role against B[a]P-induced oxidative stress and behavioral deficits. The histopathological studies showed the percentage change of pyknotic cell counts in the Periventricular Gray Zone region of the Optic Tectum was 1.74 folds high in B[a]P treated animals as compared to control. Furthermore, the treatment of SSE and crocin reduced the pyknosis process induced by B[a]P-mediated neurodegeneration, possibly due to a better protective mechanism. Future studies may reveal the detailed mechanisms of action of potent SSE and crocin like bioactive compounds having neuroprotective potentials against neurodegenerative diseases.

Assessment of cellular damage with cytome assay among environmental/occupational triazole

The use of triazole fungicides is common in Minas Gerais, Brazil. However, the risk arising from excessive and often unprotected exposure can be harmful to farmers. Therefore, we evaluated volunteers, exposed to triazole fungicides for cellular damage caused by this pesticide. In the buccal micronucleus cytome assay (BMCyt), cells were analyzed. Urinary triazoles were analyzed by the Liquid-Liquid Extraction coupled with Gas-chromatography/mass-spectrometry (LLE-GC/MS). Statistical differences were found for all cell types evaluated in residents of rural areas (n = 145). Analysis of variance showed statistical difference in kariolytic and pyknotic cells, between the groups of men and women living in rural areas, with higher incidence in the male group. Likewise, higher concentrations triazoles in urine samples in the male group were observed. Greater cellular damage suggests increases in DNA damage, chromossomal instability and cell deaths. The results showed the urgency of the public management with the implementation of measures to minimize the pesticides exposure.

Retinal regeneration after injury induced by gamma-ray irradiation during early embryogenesis in medaka, Oryzias latipes

Purpose Zebrafish, a small fish model, exhibits a multipotent ability for retinal regeneration after damage throughout its lifetime. Compared with zebrafish, birds and mammals exhibit such a regenerative capacity only during the embryonic period, and this capacity decreases with age. In medaka, another small fish model that has also been used extensively in biological research, the retina’s inner nuclear layer (INL) failed to regenerate after injury in the hatchling at eight days postfertilization (dpf). We characterized the regenerative process of the embryonic retina when the retinal injury occurred during the early embryonic period in medaka. Methods We employed a 10 Gy dose of gamma-ray irradiation to initiate retinal injury in medaka embryos at 3 dpf and performed histopathological analyses up to 21 dpf. Results One day after irradiation, numerous apoptotic neurons were observed in the INL; however, these neurons were rarely observed in the ciliary marginal zone and the photoreceptor layer. Numerous pyknotic cells were clustered in the irradiated retina until two days after irradiation. These disappeared four days after irradiation, but the abnormal bridging structures between the INL and ganglion cell layer (GCL) were present until 11 days after irradiation, and the neural layers were completely regenerated 18 days after irradiation. After gamma-ray irradiation, the spindle-like Müller glial cells in the INL became rounder but did not lose their ability to express SOX2. Conclusions Irradiated retina at 3 dpf of medaka embryos could be completely regenerated at 18 days after irradiation (21 dpf), although the abnormal layer structures bridging the INL and GCL were transiently formed in the retinas of all the irradiated embryos. Four days after irradiation, embryonic medaka Müller glia were reduced in number but maintained SOX2 expression as in nonirradiated embryos. This finding contrasts with previous reports that 8 dpf medaka larvae could not fully regenerate damaged retinas because of loss of SOX2 expression.

Postmortem Ultrastructural Analysis of the Retina from COVID-19 Deceased Patients

ABSTRACT Purpose COVID-19 (coronavirus disease 2019) is an infectious disease caused by SARS-CoV-2, first reported in 2019 in Wuhan, China. Among the common complications is a pro-inflammatory and hypercoagulative response that compromises the vasculature among various organs. Methods In this report, we present the postmortem retinal findings of five patients observed by means of optical microscopy and transmission and scanning electron microscopy techniques. Results Clinical manifestations such as retinal hemorrhages and exacerbated inflammatory infiltrate, altered ultra structure with swollen mitochondria and pyknotic cells in both layers of the retina were observed in all analyzed eyes. Conclusion Our data point to the fragility of this tissue in cases of severe COVID-19.

Ecotoxicological evaluation of the UV-filter octocrylene (OC) in embryonic zebrafish (Danio rerio): Developmental, biochemical and cellular biomarkers

Octocrylene (OC), an UV-filter (OUVF) is used in many cosmetic products to protect the skin against the harmful effects of UV radiation. Octocrylene has been detected in the environment and become an emerging contaminant of concern. However, the eco-toxicological data on octocrylene and their molecular effects and mechanism of action on freshwater fish are very limited. In this research work, the potential toxicity of octocrylene and its mechanisms on morphology, antioxidant and AChE activity, apoptosis, and histopathological changes were investigated in embryonic zebrafish (Danio rerio) at different concentrations (5, 50 and 500 μg/L). Embryos/larvae (96 hpf) treated with 50 and 500 μg/L of OC caused developmental abnormalities, and decreased hatching rate and heartbeat rate. The oxidative damage (LPO) and antioxidant enzyme (SOD, CAT and GST) activities were apparently elevated (P < 0.05) at the highest test concentration (500 μg/L). However, acetylcholinesterase (AChE) activity was significantly inhibited at the highest test concentration. Also, OC induced apoptosis in a dose-dependent manner. The zebrafish exposed to 50 and 500 μg/L showed histopathological changes including elongated yolk sac, swim bladder inflammation, muscle cell degeneration, retinal damage and pyknotic cells. In conclusion, octocrylene has induced oxidative stress at environmentally relevant concentrations leading to developmental toxicity, neurotoxicity, and histopathological damage in zebrafish embryos/larvae.

Cell Proliferation and Cell Death Levels in the Dentate Gyrus Correlate with Home Range Size Among Adult Male Meadow Voles

Neurogenesis occurs throughout adulthood within the dentate gyrus, and evidence indicates that these new neurons play a critical role in both spatial and social memory. However, a vast majority of past research on adult neurogenesis has involved experiments with captive mice and rats, making the generalizability of results to natural settings questionable. We assessed the connection between adult neurogenesis and memory by measuring the home range size of wild-caught, free-ranging meadow voles (Microtus pennsylvanicus). Adult male voles (n = 18) were captured, fitted with radio collars, and released back into their natural habitat, where each vole’s home range was assessed using 40 radio-telemetry fixes over the course of 5 evenings. Voles were then recaptured, and brain tissue was collected. Cellular markers of cell proliferation (pHisH3, Ki67), neurogenesis (DCX), and pyknosis were labeled on histological sections and then quantified using either fluorescent or light microscopy. Voles with larger home ranges had significantly higher pHisH3+ cell densities within the granule cell layer and subgranular zone (GCL + SGZ) of the dentate gyrus and higher Ki67+ cell densities in the dorsal GCL + SGZ. Voles with larger ranges also had significantly higher pyknotic cell densities in the entire GCL + SGZ and in the dorsal GCL + SGZ. These results support the hypothesis that cell proliferation and cell death within the hippocampus are involved with spatial memory formation. However, a marker of neurogenesis (DCX+) was not correlated with range size, suggesting that there may be selective cellular turnover in the dentate gyrus when a vole is ranging through its environment.

Histopathological Analysis of Nodal Disease After Chemoradiation Reveals Viable Tumor Cells as the most Important Prognostic Factor in Head and Neck Squamous Cell Carcinoma

BackgroundIn head and neck squamous cell carcinoma (HNSCC), salvage neck dissection (ND) is required after primary chemoradiation in case of residual nodal disease. Upon histopathological examination, viability of tumor cells is assessed but little is known about other prognostic histopathological features. In particular, the presence of swirled keratin debris and its prognostic value is controversial. The aim of this study is to examine histopathological parameters in ND specimens and correlate them with patient outcome to determine the relevant parameters for histopathological reporting.Materials and MethodsSalvage ND specimen from a cohort of n = 75 HNSCC (oropharynx, larynx, hypopharynx) patients with prior (chemo) radiation were evaluated on H&E stains for the following parameters: viable tumor cells, necrosis, swirled keratin debris, foamy histiocytes, bleeding residues, fibrosis, elastosis, pyknotic cells, calcification, cholesterol crystals, multinucleated giant cells, perineural, and vascular invasion. Histological features were correlated with survival outcomes.ResultsOnly the presence / amount (area) of viable tumor cells correlated with a worse clinical outcome (local and regional recurrence-free survival, (LRRFS), distant metastasis-free survival, disease-specific survival, and overall survival, p < 0.05) in both the univariable and multivariable analyses.ConclusionWe could confirm the presence of viable tumor cells as a relevant negative prognostic factor after (chemo) radiation. The amount (area) of viable tumor cells further substratified patients with worse LRRFS. None of the other parameters correlated with a distinctive worse outcome. Importantly, the presence of (swirled) keratin debris alone should not be considered viable tumor cells (ypN0).

Radioprotective potential of probiotics against gastrointestinal and neuronal toxicity: a preclinical study

PurposeRadiotherapy is a critical component of cancer treatment, along with surgery and chemotherapy. Approximately, 90% of cancer patients undergoing pelvic radiotherapy show gastrointestinal (GI) toxicity, including bloody diarrhea, and gastritis, most of which are associated with gut dysbiosis. In addition to the direct effect of radiation on the brain, pelvic irradiation can alter the gut microbiome, leading to inflammation and breakdown of the gut–blood barrier. This allows toxins and bacteria to enter the bloodstream and reach the brain. Probiotics have been proven to prevent GI toxicity by producing short-chain fatty acids and exopolysaccharides beneficial for protecting mucosal integrity and oxidative stress reduction in the intestine and also shown to be beneficial in brain health. Microbiota plays a significant role in maintaining gut and brain health, so it is important to study whether bacterial supplementation will help in maintaining the gut and brain structure after radiation exposure.MethodsIn the present study, male C57BL/6 mice were divided into control, radiation, probiotics, and probiotics + radiation groups. On the 7th day, animals in the radiation and probiotics + radiation groups received a single dose of 4 Gy to whole-body. Posttreatment, mice were sacrificed, and the intestine and brain tissues were excised for histological analysis to assess GI and neuronal damage.ResultsRadiation-induced damage to the villi height and mucosal thickness was mitigated by the probiotic treatment significantly (p < 0.01). Further, radiation-induced pyknotic cell numbers in the DG, CA2, and CA3 areas were substantially reduced with bacterial supplementation (p < 0.001). Similarly, probiotics reduced neuronal inflammation induced by radiation in the cortex, CA2, and DG region (p < 0.01). Altogether, the probiotics treatment helps mitigate radiation-induced intestinal and neuronal damage.ConclusionIn conclusion, the probiotic formulation could attenuate the number of pyknotic cells in the hippocampal brain region and decrease neuroinflammation by reducing the number of microglial cells.