Controlled changes in mitochondrial biogenesis and morphology are required for cell survival and homeostasis, but the molecular mechanisms are largely unknown. Here, male and female prepubertal mice (P21) with insulin and IGF1 receptors deletions in steroidogenic tissues (Insr/Igf1r-DKO) were used to investigate transcription of the key regulators of mitochondrial biogenesis (Ppargc1a, Ppargc1b, Pparg, Nrf1, Tfam) and architecture (Opa1, Mfn1, Mfn2) in Leydig cells, ovaries and adrenals. Results showed that the expression of PGC1, a master regulator of mitochondrial biogenesis and integrator of environmental signals, and its downstream target Tfam, significantly decreased in androgen-producing Leydig cells. This is followed by reduction of Mtnd1, an mtDNA encoded transcript whose core subunit belongs to the minimal assembly required for catalysis. The same markers remained unchanged in ovaries. In contrast, in adrenals, the pattern of transcripts for mitochondrial biogenesis markers was the same in both sexes, but opposite from that observed in Leydig cells. The level of transcripts for markers of mitochondrial architecture (Mfn1, Mfn2) significantly increased in Leydig cells from Insr/Igf1r-DKO, but not in ovaries. This was followed by mitochondrial morphology disturbance, suggesting that the mitochondrial phase of steroidogenesis could be affected. Indeed, basal and pregnenolone stimulated progesterone productions in the mitochondria of Leydig cells from Insr/Igf1r-DKO decreased more than androgen production, and were barely detectable. Our results are the first to show that INSR and IGF1R are important for mitochondrial biogenesis in gonadal steroidogenic cells of prepubertal males, but not females and they serve as important regulators of mitochondrial architecture and biogenesis markers in Leydig cells.

Background and Objectives: The COVID-19 pandemic has led to significant changes globally, which has also affected patients with type 1 diabetes mellitus (T1DM). This study aimed to determine the incidence of T1DM and the characteristics of diabetic ketoacidosis (DKA) during the pandemic comparing it to pre-pandemic period. Materials and Methods: Data from patients <19 years with newly diagnosed T1DM between 1st January 2017 and 31st December 2021 from four regional centers in Vojvodina were retrospectively collected and analyzed. Results: In 2021, the highest incidence of T1DM in the last five years was recorded, 17.3/100,000. During the pandemic period (2020–2021), there were 99 new-onset T1DM, of which 42.4% presented in DKA, which is significantly higher than in the pre-pandemic period (34.1%). During the pandemic, symptom duration of T1DM lasted significantly longer than before the COVID-19 period. At the age of 10–14 years, the highest incidence of T1DM and COVID-19, the highest frequency rate of DKA, and severe DKA were observed. Conclusions: The pandemic is associated with a high incidence rate of T1DM, longer duration of symptoms of T1DM, a high frequency of DKA, and a severe DKA at diagnosis. Patients aged 10–14 years are a risk group for the occurrence of T1DM with severe clinical presentation. Additional studies are needed with a longer study period and in a wider geographical area, with data on exposure to COVID-19 infection, the permanence of new-onset T1DM, and the psychosocial impact of the pandemic.

(1) Background: home-based spirometry, as a form of telemedicine in pulmonology, was previously successfully implemented in clinical practice in developed countries. However, experiences from developing countries are lacking. The aim of this study was to assess the reliability and feasibility of home-based spirometry in patients with interstitial lung diseases from Serbia. (2) Methods: 10 patients were given a personal hand-held spirometer with operating instructions and asked to perform daily domiciliary spirometry for the next 24 weeks. The K-BILD questionnaire was used to assess patients’ quality of life, while the questionnaire designed specifically for this study was used to assess their attitudes toward and satisfaction with domiciliary spirometry. (3) Results: there was a significant positive correlation between office- and home-based spirometry at the beginning (r = 0.946; p < 0.001) and end of the study (r = 0.719; p = 0.019). The compliance rate was nearly 70%. The domiciliary spirometry did not affect patients’ overall quality of life or anxiety levels, as measured via different domains of the K-BILD. Patients expressed positive experiences and high satisfaction with the home spirometry program. (4) Conclusions: home-based spirometry may represent a reliable form of spirometry, exploited in routine clinical practice; however, additional research in developing countries with a larger sample size is required.

Circadian desynchrony, caused by a misalignment between the internal biological clock and environmental light cues, is increasingly prevalent in adolescents due to irregular light exposure and social pressures. However, its impact on reproductive maturation remains poorly understood. In this study, the effects of chronic circadian disruption, induced by the 223 light regimen (two days of constant light, two days of constant darkness, and three days of a 14:10 h light-dark cycle), were examined in juvenile and peripubertal male rats (postnatal days 21-49). Gene expression profiles associated with Leydig cell maturation, including steroidogenic, mitochondrial, and clock-related genes, as well as markers of germ cell differentiation, were analyzed alongside functional mitochondrial parameters in Leydig cells. Under control conditions, Leydig cell maturation was marked by increased expression of core clock genes, steroidogenic enzymes (Star, Cyp11a1, Hsd3b1/2), and mitochondrial biogenesis and dynamics markers (Tfam, Nrf1, Cytc, Opa1, Mfn2). These transcriptional changes coincided with rising mitochondrial content, membrane potential, ATP levels, serum androgens, and progression of spermatogenesis. Conversely, the 223-regimen disrupted behavioral rhythms, reduced circulating melatonin, blunted expression of maturation-associated genes, and shifted the acrophase of key steroidogenic and circadian transcripts in 49-day-old rats, indicating altered Leydig cell rhythmicity. These molecular disruptions were accompanied by decreased testosterone levels, altered expression of spermatid differentiation genes (Tnp1 and Prm2), and a reduction in the number of elongated spermatids at stage VII of spermatogenesis. In conclusion, circadian misalignment disrupts endocrine and transcriptional coordination during Leydig cell development, underscoring the vulnerability of pubertal reproductive maturation to environmental light disturbances.

The thymus is the primary lymphoid organ involved in the regulation of the immune and endocrine systems. It is particularly sensitive to various types of stress, which induce its atrophy. This study deals with the effect of repeated restraint stress on the weight, proliferation and apoptosis of the thymus in mice. During restraint, the animals were placed in 50-mL conical plastic tubes for 2 h every day for either 10 or 20 consecutive days. A significant reduction in thymus weight along with decreased cellularity and pronounced atrophy of the cortical part of the thymus was observed in animals exposed to repeated tube-restraint stress for 10 and 20 consecutive days. The observed changes in the thymus were the same, regardless of the number of days of exposure to stress. These findings provide a more comprehensive view of repeated tube-restraint, with special emphasis on its duration on stress-induced thymus atrophy. The presented findings could serve as a basis for further studies aimed at identifying the mechanisms responsible for the adaptive response of the thymus after repeated exposure to stress.