Sunil J. Wimalawansa

Prof. Sunil J. Wimalawansa

North Brunswick, Jersey City, New Jersey, USA
orcid
Dr Sunil J Wimalawasa, MD, PhD. (Distinguish University Prof...

Research Focus & Metrics

Academic Career Length

46Years (1981-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 May 2019 in Biology
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Sunil J. WimalawansaSunil J. Wimalawansa
Sunil J. Wimalawansa
Recent advances in vitamin D research indicate that this vitamin, a secosteroid hormone, has beneficial effects on several body systems other than the musculoskeletal system. Both 25 dihydroxy vitamin D [25(OH)2D] and its active hormonal form, 1,25-dihydroxyvitamin D [1,25(OH)2D] are essential for human physiological functions, including damping down inflammation and the excessive intracellular oxidative stresses. Vitamin D is one of the key controllers of systemic inflammation, oxidative stress and mitochondrial respiratory function, and thus, the aging process in humans. In turn, molecular and cellular actions form 1,25(OH)2D slow down oxidative stress, cell and tissue damage, and the aging process. On the other hand, hypovitaminosis D impairs mitochondrial functions, and enhances oxidative stress and systemic inflammation. The interaction of 1,25(OH)2D with its intracellular receptors modulates vitamin D–dependent gene transcription and activation of vitamin D-responsive elements, which triggers multiple second messenger systems. Thus, it is not surprising that hypovitaminosis D increases the incidence and severity of several age-related common diseases, such as metabolic disorders that are linked to oxidative stress. These include obesity, insulin resistance, type 2 diabetes, hypertension, pregnancy complications, memory disorders, osteoporosis, autoimmune diseases, certain cancers, and systemic inflammatory diseases. Vitamin D adequacy leads to less oxidative stress and improves mitochondrial and endocrine functions, reducing the risks of disorders, such as autoimmunity, infections, metabolic derangements, and impairment of DNA repair; all of this aids a healthy, graceful aging process. Vitamin D is also a potent anti-oxidant that facilitates balanced mitochondrial activities, preventing oxidative stress-related protein oxidation, lipid peroxidation, and DNA damage. New understandings of vitamin D-related advances in metabolomics, transcriptomics, epigenetics, in relation to its ability to control oxidative stress in conjunction with micronutrients, vitamins, and antioxidants, following normalization of serum 25(OH)D and tissue 1,25(OH)2D concentrations, likely to promise cost-effective better clinical outcomes in humans.

1 January 1997 in Critical Reviews™ in Neurobiology
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Sunil J. WimalawansaSunil J. Wimalawansa
Sunil J. Wimalawansa
The calcitonin gene peptide superfamily consists of calcitonin (CT), calcitonin gene-related peptide (CGRP), and amylin. CT and CGRP derive from the CT/CGRP gene, which is encoded on chromosome 11. Alternative splicing of the primary RNA transcript leads to the translation of CGRP and CT peptides in a tissue-specific manner. CGRP (a 37-amino-acid neuropeptide) and its receptors are widely distributed in the body, and it is the most potent endogenous vasodilatory peptide discovered so far. CT (a 32-amino-acid peptide) is, however, a hormone primarily involved in protecting the skeleton during periods of "calcium stress" such as growth, pregnancy, and lactation. CT derives from the C cells of the thyroid gland and is the most potent peptide inhibitor of osteoclast-mediated bone resorption. Therefore, treatment with CT is highly effective for conditions associated with increased bone turnover such as Paget's disease, osteoporosis, Sudeck's atrophy, and hypercalcemia. Amylin (a 37-amino-acid peptide) is generated from a gene located on chromosome 12 (thought to be an evolutionary duplication of chromosome 11) and shares 46% amino acid sequence homology with CGRP and 20% with human CT. Amylin is predominantly located in the β cells of the islets of the pancreas and may be involved in the pathogenesis of type II diabetes by deposition as amyloid within the pancreas, leading to β cell destruction. Adrenomedullin, a recently discovered 52-amino-acid vasoactive peptide from adrenal tissue, shares 24% homology with CGRP and is also a member of this superfamily of peptides. A portion of the B-chain of insulin is strongly homologous to these four peptides. Not only does adrenomedullin (13-52) show 24% amino acid homology with CGRP, it also has a biological activity profile similar to that of CGRP. CGRP, CT, and amylin are related to the insulin gene superfamily of peptides, which may all have diverged from a common ancestral gene during evolution. When the crystallographic- and nuclear magnetic resonance-based molecular modeling of the three-dimensional structure of CGRP, CT, amylin, and adrenomedullin peptides and their receptors is available, it will lead to a greater understanding of the involvement of this family of peptides in pathophysiology. Together, CGRP, CT, amylin and adrenomedullin have overlapping biological effects owing to their structures and cross-reactivity between receptors. I propose that CT, CGRP, adrenomedullin, and amylin belong to a family of G-protein-coupled receptors (an "insulin superfamily" of peptides) and therefore share some of the characteristics of insulin, such as growth factor-like effects, and possible interaction at insulin receptor sites as an antagonist.

1 January 2018 in The Journal of Steroid Biochemistry and Molecular Biology
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Sunil J. WimalawansaSunil J. Wimalawansa
Sunil J. Wimalawansa

26 January 2025 in Nutrients
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Mohammed S. RazzaqueMohammed S. Razzaque
Mohammed S. Razzaque
Sunil J. WimalawansaSunil J. Wimalawansa
Sunil J. Wimalawansa
Minerals are essential nutrients that play critical roles in human health by regulating various physiological functions. Examples include bone development, enzyme function, nerve signaling, and the immune response. Both the deficiencies and toxicities of minerals can have significant health implications. Deficiencies in macrominerals such as calcium, magnesium, and phosphate can lead to osteoporosis (associated with falls and fractures), cardiovascular events, and neuromuscular dysfunction. Trace mineral deficiencies, such as iron and zinc. Selenium deficiency impairs oxygen transport, immune function, and antioxidant defenses, contributing to anemia, delaying wound healing, and increasing susceptibility to infectious diseases. Conversely, excessive intake of minerals can have severe health consequences. Hypercalcemia can cause kidney stones and cardiac arrhythmias as well as soft-tissue calcification, whereas excessive iron deposition can lead to oxidative stress and organ/tissue damage. Maintaining adequate mineral levels through a balanced diet, guided supplementation, and monitoring at-risk populations is essential for good health and preventing disorders related to deficiencies and toxicities. Public health interventions and education about dietary sources of minerals are critical for minimizing health risks and ensuring optimal well-being across populations. While a comprehensive analysis of all macro and micronutrients is beyond the scope of this article, we have chosen to focus on calcium, magnesium, and phosphate. We summarize the consequences of deficiency and the adverse events associated with the overconsumption of other minerals.

1 July 1985 in The Lancet
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SGSamiaI. Girgis
SamiaI. Girgis
JSJohnC. Stevenson
JohnC. Stevenson
CLCatherine Lynch
Catherine Lynch
CSColinH. Self
ColinH. Self
DMDavidW.R. Macdonald
DavidW.R. Macdonald
IMIain Macintyre
Iain Macintyre

1 April 1996 in Bone
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Journal Article
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Sunil J. WimalawansaSunil J. Wimalawansa
Sunil J. Wimalawansa
GMG De Marco
G De Marco
PGP Gangula
P Gangula
CYC Yallampalli
C Yallampalli