The clinical and genetic spectrum of autosomal-recessive TOR1A-related disorders.

In the field of rare diseases, progress in molecular diagnostics led to the recognition that variants linked to autosomal-dominant neurodegenerative diseases of later onset can, in the context of biallelic inheritance, cause devastating neurodevelopmental disorders and infantile or childhood-onset neurodegeneration. TOR1A-associated arthrogryposis multiplex congenita 5 (AMC5) is a rare neurodevelopmental disorder arising from biallelic variants in TOR1A, a gene that in the heterozygous state is associated with torsion dystonia-1 (DYT1 or DYT-TOR1A), an early-onset dystonia with reduced penetrance. While 15 individuals with AMC5-TOR1A have been reported (less than 10 in detail), a systematic investigation of the full disease-associated spectrum has not been conducted. Here, we assess the clinical, radiological and molecular characteristics of 57 individuals from 40 families with biallelic variants in TOR1A. Median age at last follow-up was 3 years (0-24 years). Most individuals presented with severe congenital flexion contractures (95%) and variable developmental delay (79%). Motor symptoms were reported in 79% and included lower limb spasticity and pyramidal signs, as well as gait disturbances. Facial dysmorphism was an integral part of the phenotype, with key features being a broad/full nasal tip, narrowing of the forehead and full cheeks. Analysis of disease-associated manifestations delineated a phenotypic spectrum ranging from normal cognition and mild gait disturbance to congenital arthrogryposis, global developmental delay, intellectual disability, absent speech and inability to walk. In a subset, the presentation was consistent with foetal akinesia deformation sequence with severe intrauterine abnormalities. Survival was 71%, with higher mortality in males. Death occurred at a median age of 1.2 months (1 week-9 years), due to respiratory failure, cardiac arrest or sepsis. Analysis of brain MRI studies identified non-specific neuroimaging features, including a hypoplastic corpus callosum (72%), foci of signal abnormality in the subcortical and periventricular white matter (55%), diffuse white matter volume loss (45%), mega cisterna magna (36%) and arachnoid cysts (27%). The molecular spectrum included 22 distinct variants, defining a mutational hotspot in the C-terminal domain of the Torsin-1A protein. Genotype-phenotype analysis revealed an association of missense variants in the 3-helix bundle domain to an attenuated phenotype, while missense variants near the Walker A/B motif as well as biallelic truncating variants were linked to early death. In summary, this systematic cross-sectional analysis of a large cohort of individuals with biallelic TOR1A variants across a wide age-range delineates the clinical and genetic spectrum of TOR1A-related autosomal-recessive disease and highlights potential predictors for disease severity and survival.

Role of vitamin D in pathogenesis and severity of COVID-19 infection.

Coronavirus disease (COVID-19) is an infectious disease caused by a new virus that causes respiratory illness. Older adults and individuals who have pre-existing chronic medical conditions are at higher risk for more serious complications from COVID-19. Hypovitaminosis D is attributed to the increased risk of lung injury and acute respiratory distress syndrome (ARDS) as well as diabetes, cardiovascular events and associated comorbidities, which are the main causes of severe clinical complications in COVID-19 patients. Considering the defensive role of vitamin D, mediated through modulation of the innate and adaptive immune system as well as inhibition of the Renin Angiotensin System (RAS), vitamin D supplementation might boost the immune system of COVID-19 patients and reduce severity of the disease in vitamin D deficient individuals.

Bi-allelic loss-of-function variants in PPFIBP1 cause a neurodevelopmental disorder with microcephaly, epilepsy, and periventricular calcifications.

PPFIBP1 encodes for the liprin-ß1 protein, which has been shown to play a role in neuronal outgrowth and synapse formation in Drosophila melanogaster. By exome and genome sequencing, we detected nine ultra-rare homozygous loss-of-function variants in 16 individuals from 12 unrelated families. The individuals presented with moderate to profound developmental delay, often refractory early-onset epilepsy, and progressive microcephaly. Further common clinical findings included muscular hyper- and hypotonia, spasticity, failure to thrive and short stature, feeding difficulties, impaired vision, and congenital heart defects. Neuroimaging revealed abnormalities of brain morphology with leukoencephalopathy, ventriculomegaly, cortical abnormalities, and intracranial periventricular calcifications as major features. In a fetus with intracranial calcifications, we identified a rare homozygous missense variant that by structural analysis was predicted to disturb the topology of the SAM domain region that is essential for protein-protein interaction. For further insight into the effects of PPFIBP1 loss of function, we performed automated behavioral phenotyping of a Caenorhabditis elegans PPFIBP1/hlb-1 knockout model, which revealed defects in spontaneous and light-induced behavior and confirmed resistance to the acetylcholinesterase inhibitor aldicarb, suggesting a defect in the neuronal presynaptic zone. In conclusion, we establish bi-allelic loss-of-function variants in PPFIBP1 as a cause of an autosomal recessive severe neurodevelopmental disorder with early-onset epilepsy, microcephaly, and periventricular calcifications.

Expression and localization of transient receptor potential channels in the bovine uterus epithelium throughout the estrous cycle.

Transient receptor potential (TRP) channels are expressed in the endometrium but it is unknown if they are modulated through the estrous cycle (EC). This study was undertaken to identify the modulation of the TRPC gene and protein isoforms in bovine uterine epithelium, as a model for human, throughout the EC. Changes in the expression of TRPC genes in bovine uterine epithelium throughout the EC were measured using Real-Time PCR, while immunohistochemistry and immunocytochemistry were used to determine the localization of these channels. Out of the 7 members of the TRPC family, TRPC1, 2, 3, 4 and 6 genes were expressed in bovine uterine epithelial tissue and TRPC 5 and 7 were not. Gene expression levels of all TRPC isoforms underwent cyclical changes throughout the EC. Moreover, cyclical changes were detected in the protein levels of TRPC1 and TRPC6 throughout the EC. These findings show that TRPC channels are modulated through the EC and therefore may have a role in reproductive events.

Evaluation of promoter methylation status of MLH1 gene in Iranian patients with colorectal tumors and adenoma polyps.

AIM: The aim of this study was to evaluate the methylation status of the promoter region of MLH1 gene in colorectal cancer (CRC) and its precursor lesions as well as elucidate its association with various clinicopathological characteristics among Iranian population. BACKGROUND: Epigenetic silencing of mismatch repair genes, such as MLH1, by methylation of CpG islands of their promoter region has been proved to be an important mechanism in colorectal carcinogenesis. METHODS: Fifty colorectal cancer and polyp tissue samples including 13 Primary colorectal tumor and 37 Adenoma polyp samples were enrolled in this study. Methylation-specific polymerase chain reaction (MSP) was performed to find the frequency of MLH1 Promoter Methylation. RESULTS: Promoter methylation of MLH1 gene was detected in 5 out of 13 tumor tissues and 4 out of 37 adenoma polyp. The frequency of MLH1 methylation in tumor samples was significantly higher compared to that in polyp tissues (P= 0.026). No significant association was observed between MLH1 promoter methylation and clinicopathological characteristics of the patients. CONCLUSION: The frequency of MLH1 promoter methylation in CRC and colon polyp was 18%. Our findings indicated that methylation of MLH1 promoter region alone cannot be considered as a biomarker for early detection of CRC.

Expression and function of transient receptor potential channels in the female bovine reproductive tract.

The epithelium lining the oviduct is critical for early reproductive events, many of which are mediated via intracellular calcium ions. Despite this, little is known about the regulation of calcium homeostasis in the oviductal epithelium. Epithelial transient receptor potential channels (TRPCs) modulate calcium flux in other tissues, and their expression and functional regulation have therefore been examined using the bovine oviduct as a model for the human. The effects of FSH, LH, 17ß-estradiol, and progesterone on TRPCs expression and intracellular calcium flux were determined. Transient receptor potential channels 1, 2, 3, 4, and 6 were expressed in the bovine reproductive tract, and their gene expression varied throughout the estrous cycle. In more detailed studies undertaken on TRPC1 and 6, we show that protein expression varied through the estrus cycle; specifically, 17ß-estradiol, FSH, and LH individually and in combination upregulated TRPC1 and 6 expression in cultured bovine oviduct epithelial cells although progesterone antagonized these effects. Functional studies showed changes in calcium mobilization in bovine oviduct epithelial cells were dependent on TRPCs. In conclusion, TRPC1, 2, 3, 4, and 6 are present in the epithelium lining the bovine oviduct, and TRPC1 and 6 vary through the estrous cycle suggesting an important role in early reproductive function.

Multiple mechanisms of soy isoflavones against oxidative stress-induced endothelium injury.

Diabetic vascular complications are related to a combination of oxidative stress and hyperglycemia. Here we investigate the effect and mechanism of soy isoflavones on oxidative stress-induced endothelial cell injury. Oxidative stress was modeled in primary cultured human umbilical vein endothelial cells by incubation with H(2)O(2) and high glucose. Genistein and daidzein protected the cells against H(2)O(2)-induced apoptosis and their protective actions were abolished by ICI 182780, an estrogen receptor antagonist. The inhibition of cell proliferation by oxidative stress was prevented by genistein and daidzein under normal glucose conditions, but they were less effective at high glucose levels. Genistein and daidzein upregulated the estrogen receptor ERbeta and increased Bcl-2 expression. Silencing of Bcl-2 with siRNA abolished the protection of genistein. Moreover, inhibition of the PI3K and Rho A/Rho kinase pathways by wortmannin and Y-27632 altered the effects of genistein and daidzein on cell survival. We conclude that oxidative stress-induced apoptosis and cell proliferation inhibition can be prevented by soy isoflavones via the regulation of ERbeta and Bcl-2/Bax expression and modulation of cell survival signaling, such as the PI3K pathway. These findings imply that multiple mechanisms are involved in the beneficial effects of soy isoflavone supplements for diabetic endothelial injury.