Effect of perinatal and postnatal thiamine deficiency on auditory pathway of the Wistar-Albino rats

Abstract Objective: In this study, we created an animal model to demonstrate the effects of thiamine on the hearing pathways of new-borns during pregnancy and lactation by inducing a dietary thiamine deficiency in the mother. Methods: The study included 16 female Wistar albino rats. The animals were separated into four groups and provided the appropriate amounts of dietary thiamine according to their groups during pre-pregnancy, pregnancy, and lactation periods. Three pups from each mother were included in the study, and 12 pups were selected from each group. On the fortieth day after birth, the auditory pathways of 48 pups in the 4 groups were examined electro physiologically and ultra-structurally. Results: In Group N-N, morphology of hair cells stereocilia degeneration was not obtained in all turns of cochlea. In Group N-T, Inner Hair Cells (IHCs) and Outher Hair Cells (OHCs) stereocilia didn't show degeneration in all turns of cochlea but had rupture inrows of HCs stereocilia. In group T-N IHCs stereocilia less degeneration was observed in all turns of cochlea. OHC stereocilia partial loss was observed only in basal turn of cochlea. In Group T-T IHCs stereocilia was observed less degeneration and rupture in all turns of cochlea. Conclusion: Thiamine is vital for the development of cochlear hair cells during both prenatal and postnatal periods. Even partial deficiency of thiamine causes significant degeneration to the auditory pathway. Level of evidence: The level of evidence of this article is 5. This article is an experimental animal and laboratory study.

Effect of perinatal and postnatal thiamine deficiency on auditory pathway of the Wistar-Albino rats.

OBJECTIVE: In this study, we created an animal model to demonstrate the effects of thiamine on the hearing pathways of new-borns during pregnancy and lactation by inducing a dietary thiamine deficiency in the mother. METHODS: The study included 16 female Wistar albino rats. The animals were separated into four groups and provided the appropriate amounts of dietary thiamine according to their groups during pre-pregnancy, pregnancy, and lactation periods. Three pups from each mother were included in the study, and 12 pups were selected from each group. On the fortieth day after birth, the auditory pathways of 48 pups in the 4 groups were examined electro physiologically and ultra-structurally. RESULTS: In Group N-N, morphology of hair cells stereocilia degeneration was not obtained in all turns of cochlea. In Group N-T, Inner Hair Cells (IHCs) and Outher Hair Cells (OHCs) stereocilia didn't show degeneration in all turns of cochlea but had rupture inrows of HCs stereocilia. In group T-N IHCs stereocilia less degeneration was observed in all turns of cochlea. OHC stereocilia partial loss was observed only in basal turn of cochlea. In Group T-T IHCs stereocilia was observed less degeneration and rupture in all turns of cochlea. CONCLUSION: Thiamine is vital for the development of cochlear hair cells during both prenatal and postnatal periods. Even partial deficiency of thiamine causes significant degeneration to the auditory pathway. LEVEL OF EVIDENCE: The level of evidence of this article is 5. This article is an experimental animal and laboratory study.

Acute dental pain elevates salivary oxytocin in women: a risk factor during pregnancy.

Irreversible pulpitis is an acute, brief, and painful condition. Oxytocin, cortisol, and secretory immunoglobulin A (sIgA) are released by the body in response to pain and emotional stress. The aim of this study was to investigate the expression of salivary cortisol, sIgA, and oxytocin among patients with irreversible pulpitis. This was an ethically approved case-control study comparing 90 cases of irreversible pulpitis and 40 healthy individuals. Five study groups were established: nonpregnant female pulpitis, pregnant female pulpitis, male pulpitis, healthy (nonpregnant) female control, and healthy male control. Pregnant women in the first trimester were enrolled in the study. Participants received both clinical and radiographic examinations, completed a simple questionnaire related to food intake, habits, and anxiety, and their pain levels were recorded on a visual analog scale in which 0 represented no pain and 10 represented the worst possible pain. Unstimulated saliva samples were collected to measure oxytocin, sIgA, and cortisol levels. Dental pulp specimens were obtained and stained with hematoxylin and eosin to evaluate the agreement between clinical and histologic pulpal diagnoses. The statistical analysis included analysis of variance and Tukey tests. The majority of patients (37%) recorded a score of 8 (severe pain) on the visual analog scale, while a score of 10 (worst possible pain) was recorded only by pregnant women (3%). There was no statistically significant difference among healthy subjects for all salivary samples. Oxytocin levels increased significantly in nonpregnant (P < 0.5) and pregnant (P < 0.001) women with pulpitis. Cortisol (P < 0.01) and sIgA (P < 0.001) levels were significantly elevated only in pregnant women with pulpitis. The results of the present study indicate that acute dental pain during pregnancy can be considered as a pregnancy risk factor because of the resulting elevated oxytocin and cortisol levels.

Lycopene inhibits caspase-3 activity and reduces oxidative organ damage in a rat model of thermal injury.

Oxidative stress has been implicated in various pathological processes including burn induced multiple organ damage. This study investigated the effects of lycopene treatment against oxidative injury in rats with thermal trauma. Under ether anesthesia, shaved dorsum of the rats was exposed to 90°C bath for 10s to induce burn and treated either vehicle (olive oil) or lycopene (50mg/kg orally). Rats were decapitated 48 h after injury and the tissue samples from lung and kidney were taken for histological analysis and the determination of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO), superoxide dismutase (SOD), catalase (CAT) and caspase-3 activities. Proinflammatory cytokines, TNF-α and IL-1ß, were assayed in blood samples. Severe skin scald injury caused a significant decrease in GSH levels, SOD and CAT activities, and significant increases in MDA levels, MPO and caspase-3 activities of tissues. Similarly, plasma TNF-α and IL-1ß were elevated in the burn group as compared to the control group. Lycopene treatment reversed all these biochemical indices. According to the findings of the present study, lycopene possesses antiinflammatory, antiapoptotic and antioxidant effects that prevents burn-induced oxidative damage in remote organs.