Resveratrol protects against inorganic arsenic-induced oxidative damage and cytoarchitectural alterations in female mouse hippocampus.

Prolonged inorganic arsenic (iAs) exposure is widely associated with brain damage particularly in the hippocampus via oxidative and apoptotic pathways. Resveratrol (RES) has gained considerable attention because of its benefits to human health. However, its neuroprotective potential against iAs-induced toxicity in CA1 region of hippocampus remains unexplored. Therefore, we investigated the neuroprotective efficacy of RES against arsenic trioxide (As2O3)-induced adverse effects on neuronal morphology, apoptotic markers and oxidative stress parameters in mouse CA1 region (hippocampus). Adult female Swiss albino mice of reproductive maturity were orally exposed to either As2O3 (2 and 4 mg/kg bw) alone or in combination with RES (40 mg/kg bw) for a period of 45 days. After animal sacrifice on day 46, the perfusion fixed brain samples were used for the observation of neuronal morphology and studying the morphometric features. While the freshly dissected hippocampi were processed for biochemical estimation of oxidative stress markers and western blotting of apoptosis-associated proteins. Chronic iAs exposure led to significant decrease in Stratum Pyramidale layer thickness along with reduction in cell density and area of Pyramidal neurons in contrast to the controls. Biochemical analysis showed reduced hippocampal GSH content but no change in total nitrite (NO) levels following iAs exposure. Western blotting showed apparent changes in the expression levels of Bax and Bcl-2 proteins following iAs exposure, however the change was statistically insignificant. Contrastingly, iAs +RES co-treatment exhibited substantial reversal in morphological and biochemical observations. Together, these findings provide preliminary evidence of neuroprotective role of RES on structural and biochemical alterations pertaining to mouse hippocampus following chronic iAs exposure.

Unilateral Variation in Extensor digitorum longus muscle.

During a routine dissection of an adult embalmed male cadaver for educational purpose in the department of anatomy at AIIMS, New Delhi, India, a rare unilateral variation of extensor digitorum longus (EDL) was found which is a muscle of anterior compartment of the leg. There was a split tendon of EDL muscle in the anterior compartment of left leg which became a common tendon in front of the ankle joint. This common tendon of EDL muscle again divided into four slips and were inserted in to the lateral four toes. In the upper part of the leg, the anterior tibial vessel and deep fibular nerve lie between the EDL and tibialis anterior. Knowledge of this type of anomaly is useful in diagnosis and treatment of compartmental syndrome. One of the tendon from the split tendon of EDL muscle can be used as a graft in tendon replacement surgeries. The split tendon may also be capable for some precise movements of the toes.

Lumbar sympathetic chain: anatomical variation and clinical perspectives.

The sympathetic and parasympathetic nervous systems constitute the autonomic nervous system which controls the entropy of the body and maintain the equilibrium. The sympathetic chain forms a definitive anatomic entity which is quite variable with respect to its position and the number of ganglia. The sympathetic nervous system causes vasoconstriction and thus forms the basis of Lumbar sympathetic surgeries being performed in patients with peripheral vascular diseases. The anatomic variations in this region hence gains immense importance for the operating surgeons and consulting radiologists. In the present study, the rami communicantes of either side of lumbar sympathetic chain crossed the common iliac arteries from lateral to medial side and united in front of first piece of sacrum. These rami communicantes encircled the right gonadal artery and could be a threat to the gonadal vascularity causing infertility. This was an unusual feature of the lumbar sympathetic chain and its rami communicantes that were noted in this particular case.

Role of neurokinin type 1 receptor in nociception at the periphery and the spinal level in the rat.

OBJECTIVES: Noxious stimuli activate small to medium-sized dorsal root ganglion (DRG) neurons. Intense noxious stimuli result in the release of substance P (SP) from the central terminals of these neurons. It binds to the neurokinin type 1 receptor (NK1r) and sensitises the dorsal horn neurons. SP is also released from the peripheral terminals leading to neurogenic inflammation. However, their individual contribution at spinal and peripheral levels to postincisional nociception has not been delineated as yet. METHODS: Sprague-Dawley rats were administered different doses (3-100 µg) of an NK1r antagonist (L760735) by intrathecal (i.t.) route before hind paw incision. On the basis of its antinociceptive effect on guarding behaviour, the 30 µg dose was selected for further study. In different sets of animals, this was administered i.t. (postemptive) and intrawound (i.w.). Finally, in another group, drug (30 µg) was administered through both i.t and i.w. routes. The antinociceptive effect was assessed and compared. Expression of SP was examined in the spinal cord. Intrawound concentration of SP and inflammatory mediators was also evaluated. RESULTS: Postemptive i.t. administration significantly attenuated guarding and allodynia. Guarding was alone decreased after i.w. drug treatment. Combined drug administration further attenuated all nociceptive parameters, more so after postemptive treatment. Expression of SP in the spinal cord decreased post incision but increased in the paw tissue. Inflammatory mediators like the nerve growth factor also increased after incision. CONCLUSION: In conclusion, SP acting through the NK1r appears to be an important mediator of nociception, more so at the spinal level. These findings could have clinical relevance.

Favorably skewed X-inactivation accounts for neurological sparing in female carriers of Menkes disease.

Classical Menkes disease is an X-linked recessive neurodegenerative disorder caused by mutations in ATP7A, which is located at Xq13.1-q21. ATP7A encodes a copper-transporting P-type ATPase and plays a critical role in development of the central nervous system. With rare exceptions involving sex chromosome aneuploidy or X-autosome translocations, female carriers of ATP7A mutations are asymptomatic except for subtle hair and skin abnormalities, although the mechanism for this neurological sparing has not been reported. We studied a three-generation family in which a severe ATP7A mutation, a 5.5-kb genomic deletion spanning exons 13 and 14, segregated. The deletion junction fragment was amplified from the proband by long-range polymerase chain reaction and sequenced to characterize the breakpoints. We screened at-risk females in the family for this junction fragment and analyzed their X-inactivation patterns using the human androgen-receptor (HUMARA) gene methylation assay. We detected the junction fragment in the proband, two obligate heterozygotes, and four of six at-risk females. Skewed inactivation of the X chromosome harboring the deletion was noted in all female carriers of the deletion (n = 6), whereas random X-inactivation was observed in all non-carriers (n = 2). Our results formally document one mechanism for neurological sparing in female carriers of ATP7A mutations. Based on review of X-inactivation patterns in female carriers of other X-linked recessive diseases, our findings imply that substantial expression of a mutant ATP7A at the expense of the normal allele could be associated with neurologic symptoms in female carriers of Menkes disease and its allelic variants, occipital horn syndrome, and ATP7A-related distal motor neuropathy.

Research challenges in central nervous system manifestations of inborn errors of metabolism.

The Research Challenges in CNS Manifestations of Inborn Errors of Metabolism workshop was designed to address challenges in translating potential therapies for these rare disorders, and to highlight novel therapeutic strategies and innovative approaches to CNS delivery, assessment of effects and directions for the future in the treatment of these diseases. Therapies for the brain in inborn errors represent some of the greatest challenges to translational research due to the special properties of the brain, and of inborn errors themselves. This review covers the proceedings of this workshop as submitted by participants. Scientific, ethical and regulatory issues are discussed, along with ways to measure outcomes and the conduct of clinical trials. Participants included regulatory and funding agencies, clinicians, scientists, industry and advocacy groups.

Non-random maternal X-chromosome inactivation associated with PHACES.

The acronym PHACES is used to describe the association of posterior fossa malformations, hemangiomas, arterial anomalies (cardiovascular or cerebrovascular), coarctation of the aorta and cardiac defects, eye abnormalities, and sternal or ventral defects. We report a female patient with an uncommon variant of this neurocutaneous disorder who manifested a sternal cleft; supraumbilical raphe; hemangiomas of the face, chest, and extremities; micrognathia and cerebrovascular anomalies. A literature review of PHACES patients with both sternal cleft and supraumbilical raphe showed a marked female predilection. Taken together with cases of sternal cleft, supraumbilical raphe and facial hemangiomas tabulated by Gorlin et al. (1994), 91% (40/44) of patients are female. One affected male died shortly after birth. We hypothesized that the gender bias in PHACES results from mutation in an X-linked dominant gene often lethal in males, and performed X-inactivation analysis of the polymorphic androgen receptor locus in this family. We documented consistently skewed X-inactivation (80%/20% in two independent analyses) in the unaffected mother and consistently random X-inactivation (47:53 and 61:39 in independent analyses) in the proband. These findings are consistent with favorably skewed X-inactivation producing a normal maternal phenotype, a phenomenon documented in X-linked dominant Rett syndrome.

Copper-replacement treatment for symptomatic Menkes disease: ethical considerations.

We describe a child with classical Menkes disease with a novel ATP7A mutation, intractable seizures, severe hypotonia and developmental delay, hypopigmentation of the skin and hair, and failure to thrive, who was treated with daily subcutaneous copper histidine injections for 2(1/2) years, beginning at 15 months of age. He became seizure-free and pigmentation of his skin and hair darkened, but he continued to have severe developmental delays. His condition remains stable 8 months after stopping treatment. We review the ethical aspects of offering copper treatment for Menkes disease infants diagnosed after neurological symptoms become manifest. These include (1) the prospect for any benefits, (2) the potential risks and discomforts, (3) the parents' wishes with respect to treatment, (4) the family's understanding of the treatment's potential futility, (5) the family's understanding of the investigational nature of this treatment, (6) the potential for treatment to have an adverse impact on unaffected family members, (7) whether the ultimate decision regarding treatment should rest with health care providers or with the patient's parents, and (8) the duration of treatment. The ethical issues encountered in providing possibly futile treatment in this difficult disorder seem relevant to other pediatric medical conditions as well.

Genotyping of two mutations in the HFE gene using single-base extension and high-performance liquid chromatography.

Currently, a major focus of human genetics is the utilization of single-nucleotide polymorphisms for clinical diagnostics, whole-genome linkage disequilibrium screens to identify common disease genes such as Alzheimer disease, determination of the recent evolutionary history of a species, and the process of speciation. We have examined single-nucleotide extension coupled with high-performance liquid chromatography as a method to simultaneously genotype two SNPs occurring in the coding region of the HFE gene that produce clinical effects. This assay allows concurrent genotyping of the C282Y and H63D mutations in 11 min and is 100% concordant with current testing methods for both of these mutations.

Novel method for molecular detection of the two common hereditary hemochromatosis mutations.

We describe a novel molecular screening technique for hereditary hemochromatosis through which HFE genotypes at codon positions 282 and 63 are simultaneously detected. The technique combines multiplex PCR and denaturing high-performance liquid chromatography (DHPLC) and allows automated high-throughput analysis. We used this method to genotype 43 previously characterized anonymous DNA specimens in blinded fashion and found multiplex PCR/DHPLC 100% accurate when compared with PCR/restriction enzyme digestion, yet far more efficient.

Diagnosis and therapy of Menkes syndrome, a genetic form of copper deficiency.

In the 25 y since copper deficiency was first delineated in persons with Menkes syndrome, advances in our understanding of the clinical, biochemical, and molecular aspects of this rare disorder have surpassed progress in the design of effective therapies. In contrast with purely nutritional copper deficiency, in which copper replacement can be curative, the nature of the basic defect in Menkes syndrome suggests that corrective efforts are likely to be more complicated, a point supported by the cumulative literature on this topic as well as by emerging molecular data. In this paper, certain clinical, biochemical, and molecular aspects of copper histidine treatment in 25 Menkes syndrome patients at the National Institutes of Health are reviewed. The delineation of a distinctive neurochemical pattern in plasma and cerebrospinal fluid, reflecting deficiency of the copper enzyme dopamine beta-monooxygenase, is arguably the most important finding in the study of Menkes syndrome. This abnormal pattern has proven extremely reliable as a rapid diagnostic test, enabling early identification of affected infants--a fundamental requirement for improving clinical outcomes. Of 11 patients identified by prenatal or prompt postnatal testing and treated within the first 10 d of age, one walked at 14 mo of age and has normal neurodevelopment at age 3 y and another infant's early progress appears promising. However, five patients died in infancy and neurodevelopmental outcome was suboptimal in four others. Consideration of additional therapeutic strategies seems necessary, therefore, for most patients and families facing this troublesome form of copper deficiency.

Metabolic and molecular bases of Menkes disease and occipital horn syndrome.

Menkes disease and occipital horn syndrome (OHS) are related disorders of copper transport that involve abnormal neurodevelopment, connective tissue problems, and often premature death. Location of the gene responsible for these conditions on the X chromosome was indicated by pedigree analysis from the time of these syndromes' earliest descriptions. Characterization of an affected female with an X-autosomal translocation was used to identify the Menkes/OHS gene, which encodes a highly evolutionarily conserved, copper-transporting P-type ATPase. The gene normally is expressed in nearly all human tissues, and it localizes to the trans-Golgi network of cells. However, in over 70% of Menkes and OHS patients studied, expression of this gene has been demonstrated to be abnormal. Major gene deletions detectable by Southern blotting account for 15-20% of patients, and an interesting spectrum of other mutations is evident among 58 families whose precise molecular defects have been reported as of this writing. The center region of the gene seems particularly prone to mutation, and those that influence mRNA processing and splicing appear to be relatively common. Further advances in understanding the molecular and cell biological mechanisms involved in normal copper transport may ultimately yield new and better approaches to the management of these disorders.

Catecholamine phenotyping: clues to the diagnosis, treatment, and pathophysiology of neurogenetic disorders.

One purpose of clinical neurochemistry has been to indicate "activities" of catecholamine systems, by assaying levels of the effector compounds or their metabolites in body fluids such as plasma, cerebrospinal fluid, urine, or microdialysate. This review discusses a new purpose: relating specific catecholaminergic phenotypes to neurogenetic disorders. Distinctive catecholamine patterns in several neurogenetic conditions reflect enzyme deficiencies as direct or indirect effects of gene mutations. These neurochemical patterns can provide potentially important clues to the diagnosis, treatment, and pathophysiology of neurogenetic disorders. Linking genetic abnormalities with molecular mechanisms and clinical manifestations of disease represents a useful new direction in clinical neurochemistry.

Distinctive Menkes disease variant with occipital horns: delineation of natural history and clinical phenotype.

To delineate further the clinical spectrum of Menkes disease, an X-linked recessive disorder of copper transport, we studied 4 related males, ranging in age from 4-38 years, with a unique phenotype that combines manifestations of classical and mild Menkes disease and occipital horn syndrome (OHS). The propositus, and 18-year-old man, was evaluated following an intracerebral hemorrhage at age 15 years and was noted to have marked hypotonia, motor delay with mental retardation, bladder diverticula, failure to thrive, and diarrhea from infancy; seizures from age 3 years; and abnormal hair (pili torti) and face, cutis laxa, and multiple joint dislocations. Radiographic abnormalities included occipital exostoses, tortuous cerebral blood vessels with multiple branch occlusions, and hammer-shaped clavicles. Biochemical studies demonstrated reduced copper and ceruloplasmin levels in serum, and abnormal plasma catecholamine ratios. We reported previously the molecular defect in this family, a splice-site mutation that predicts formation of approximately 20% of the normal Menkes gene product [Kaler et al., 1994: Nat Genet 18:195-202]. Here, we detail the clinical course and physical features and radiographic findings in these 4 individuals, and compare their phenotype with classical and mild Menkes and OHS. Unusual Menkes disease variants such as this may escape recognition due to anomalies that appear inconsistent with the diagnosis, particularly prolonged survival and later onset of seizures. Males with mental retardation and connective tissue abnormalities should be evaluated for biochemical evidence of defective copper transport.

Successful early copper therapy in Menkes disease associated with a mutant transcript containing a small In-frame deletion.

Classical Menkes disease is a fatal X-linked neurodegenerative disorder caused by defects in a gene (MNK) that encodes a copper-transporting ATPase. Treatment with parenteral copper has been proposed for patients identified before symptoms develop. We recently described suboptimal outcomes despite early copper replacement in two classical Menkes patients whose mutation predicts little if any functional copper transporter. Here, we describe successful copper replacement therapy in a patient with Menkes disease with a splice acceptor site mutation (IVS8,AS,dup5) that causes exon-skipping and generates a mutant transcript with a small in-frame deletion in a noncritical region. The patient was diagnosed by analysis of neurochemical levels in cord blood, and parenteral copper replacement was begun at 8 days of life. Throughout infancy, he showed normal head growth, brain myelination, and age-appropriate neurodevelopment, including independent walking at 14 months of age. In contrast, his affected half-brother and first cousin with the same mutation, but who were not diagnosed and treated from an early age, showed arrested head growth, cerebral atrophy, delayed myelination, and abnormal neurodevelopment. We propose that the successful neurological outcome in this patient was related to early repletion of circulating copper levels, in combination with residual copper transport by a partially functional MNK ATPase containing the small deletion. We hypothesize that raising plasma copper concentrations in patients with Menkes disease with some residual functional gene product can increase the ligand: transporter ratio and thus alter favorably the kinetics of copper transport into and within the brain.