Prevalence of major depressive disorder and its associated factors among adult patients with neurolathyrism in Dawunt District, Ethiopia; 2022: community-based cross-sectional study

INTRODUCTION

Major Depressive Disorder (MDD) is one of the commonest mental disorders affecting more than 250 million people globally. Patients with chronic illnesses had higher risks for developing MDD than the general population. Neurolathyrism is a chronic illness characterized by lifelong incurable spastic paralysis of lower extremities; causing permanent disability. It is highly prevalent in Dawunt district, Ethiopia; with a point prevalence of 2.4%. Despite this, there were no previous studies assessing the prevalence of MDD among patients with neurolathyrism in Ethiopia.

OBJECTIVE

To assess the prevalence of MDD and to identify its associated factors among patients with neurolathyrism in Dawunt district, Ethiopia.

METHODS

A community based cross-sectional study was conducted on 260 samples in Dawunt district from February 01 to March 30/ 2021. Multistage sampling technique was used to select study participants. The patient Health Questionnaire-9 (PHQ-9) depression screening tool was used to diagnose MDD. PHQ-9 is a standardized depression screening tool and a PHQ-9 score of ≥ 10 has a sensitivity and specificity of 88.0% [95% CI (83.0-92.0%)] and 85.0% [95% CI (82.0-88.0%)] for screening MDD. Data were collected by interview; entered to EpiData version 4.2.0; exported to SPSS version 25.0 for analysis; descriptive statistics and binary logistic regression model were used; AOR with 95% CI was used to interpret the associations; and finally results were presented by texts, charts, graphs, and tables.

RESULTS

A total of 256 adult patients with neurolathyrism were participated; and the prevalence of MDD was found to be 38.7%. Being female [AOR = 3.00; 95% CI (1.15, 7.84)], living alone [AOR = 2.77; 95% CI (1.02-7.53)], being on neurolathyrism stage-3 [AOR = 3.22; 95% CI (1.09, 9.54)] or stage-4 [AOR = 4.00; 95% CI (1.28, 12.48)], stigma [AOR = 2.69; 95% CI (1.34, 5.39)], and lack of social/ family support [AOR = 3.61; 95% CI (1.80, 7.24)] were found to have statistically significant association with an increased odds of MDD; while regular exercise and ever formal counselling were found to have statistically significant association with a decreased odds of MDD.

CONCLUSION

The prevalence of MDD among neurolathyrism patients in Dawunt district was high. Lack of social support, stigma, not getting formal counselling, and not involving in regular exercise were modifiable risk factors. Therefore, social support, reducing stigma, formal counselling, and encouraging regular exercise might help to reduce the burden of MDD among neurolathyrism patients.

Prevalence of Neurolathyrism and its associated factors in Grass pea cultivation areas of Dawunt District, North-eastern Ethiopia; 2022: a community based multilevel analysis

INTRODUCTION

Neurolathyrism is an upper motor neuron disorder characterized by spastic paraparesis, which is caused by the prolonged over-consumption of grass pea. It is a devastating disease with great impacts on physical, social, mental, and economical health.

OBJECTIVE

To determine the prevalence of neurolathyrism and its associated factors in grass pea cultivation areas of Dawunt wereda.

METHODS

Community based cross-sectional study design was conducted from February 01- March 30, 2021 on 631 Households with a total of 3,350 individuals. Two-stage random sampling technique was used to select participants. Multilevel binary logistic regression was used to identify factors associated with neurolathyrism. Statistical significance was declared at p < 0.05; and AOR with 95% CI was used to interpret the results.

RESULTS

The household and population level prevalence of neurolathyrism in Dawunt district were 9.2% (7.2-11.7%) and 2.4% (2.0-2.3.0%) respectively. Age (AOR = 7.4 ( 2.6-20.6)), male sex (AOR = 7.8 (3.9, 15.4)), and marital status (AOR = 4.0 (1.3-12.8)) were the individual level variables; family size (AOR = 12.6 (3.0-52.8)), annual grass pea production (AOR = 5.0 (2.3-11.0)), ever feeding only grass pea (AOR = 8.8(3.5-22.2)), ever feeding immature seeds of grass pea (AOR = 6.28 (2.80, 14.08)), high grass pea to other cereals mixing ratio (> 3:1) (AOR = 6.1 (1.1, 33.5)) were the household level variables found to have significant association with neurolathyrism.

CONCLUSION

The prevalence of neurolathyrism was found to be high. Ever feeding only grass pea, Grass pea to other cereals mixing ratio (using ratio of 1:1 or more), and Ever feeding immature grass pea seeds were the modifiable risk factors for neurolathyrism.

Stress-related over-enhancement of the hypothalamic-pituitary-adrenal axis causes experimental neurolathyrism in rats

Neurolathyrism is a motor neuron disease that is caused by the overconsumption of grass peas (Lathyrus sativus L.) under stressful conditions. The neuro-excitatory β-N-oxalyl-L-α,β-diaminopropionic acid present in grass peas was proposed the causative agent of spastic paraparesis of the legs. Historical reports of neurolathyrism epidemics, studies of neurolathyrism animal models, and in vitro studies on the mechanism of β-N-oxalyl-L-α,β-diaminopropionic acid toxicity support the hypothesis that stress increases susceptibility to neurolathyrism. To elucidate the role of stress in neurolathyrism-induced motor dysfunction, we focused on the hypothalamic-pituitary-adrenal axis in a rodent model of neurolathyrism. Our results implicated increased glucocorticoid and neuroinflammation in the motor dysfunction (paraparesis) exhibited by the stress loaded rat models of neurolathyrism.

Prolonged consumption of grass pea (64 g/Cu/day) along with millets and other cereals causes no neurolathyrism

Objective: To assess the safe limit of L. sativus (grass pea) consumption along with cereals and millets.Methods: A community-based cross-sectional study was undertaken in three districts (Bilaspur, Durg and Raipur) of Chhattisgarh state. A total of 1500 households (HHs) were surveyed. A total of 360 split grass pea (SGP) samples were collected from all three districts for ?-ODAP analysis. Clinical examination was carried out for symptoms of neurolathyrism. Diet survey was done on 5769 HHs by 24hr recall method. Mean intake of different foods and nutrients were calculated. Based on food frequency questionnaire, HHs were separated into daily consumers of SGP along with its quantity consumed and that never consumed SGP.Results: The study revealed that 30 daily consuming and 89 never consuming HHs, in all the three districts. Daily SGP was consumed at an average of 64 g/Cu/day along with millets, cereals and vegetables. Whereas among the never consumers of SGP, mean intake of vegetables was higher than recommended intakes in addition to pulses. The average ?-ODAP content in SGP was 0.630 g%. The nutritional status of children <5 years and the adults was not significantly different between the daily SGP consumers and never consumers. Households in all the three districts, who consumed the SGP recipes, followed the method of washing, boiling, draining the excess water and cooking the pulse.Discussion: There were no adverse effects observed among daily consumers of grass pea (64 g/CU/day) along with millets, cereals and vegetables.

Proteomic Changes in Chick Brain Proteome Post Treatment with Lathyrus Sativus Neurotoxin, β-N-Oxalyl-L-α,β-Diaminopropionic Acid (L-ODAP): A Better Insight to Transient Neurolathyrism

Neurolathyrism is a neurodegenerative disorder characterized by spastic paraplegia resulting from the excessive consumption of Lathyrus sativus (Grass pea). β-N-Oxalyl-L-α,β-diaminopropionic acid (L-ODAP) is the primary neurotoxic component in this pea. The present study attempted to evaluate the proteome-wide alterations in chick brain 2 hr and 4 hr post L-ODAP treatment. Proteomic analysis of chick brain homogenates revealed several proteins involved in cytoskeletal structure, signaling, cellular metabolism, free radical scavenging, oxidative stress and neurodegenerative disorders were initially up-regulated at 2 hr and later recovered to normal levels by 4 hr. Since L-ODAP mediated neurotoxicity is mainly by excitotoxicity and oxidative stress related dysfunctions, this study further evaluated the role of L-ODAP in apoptosis in vitro using human neuroblastoma cell line, IMR-32. The in vitro studies carried out at 200 μM L-ODAP for 4 hr indicate minimal intracellular ROS generation and alteration of mitochondrial membrane potential though not leading to apoptotic cell death. L-ODAP at low concentrations can be explored as a stimulator of various reactive oxygen species (ROS) mediated cell signaling pathways not detrimental to cells. Insights from our study may provide a platform to explore the beneficial side of L-ODAP at lower concentrations. This study is of significance especially in view of the Government of India lifting the ban on cultivation of low toxin Lathyrus varieties and consumption of this lentil.

Tissue specific expression and in-silico characterization of a putative cysteine synthase gene from Lathyrus sativus L

Grass pea (Lathyrus sativus L.) is a worldwide popular pulse crop especially for its protein rich seeds with least production cost. However, the use of the crop became controversial due to the presence of non-protein amino acid, β-N-oxalyl-L-α, β-diaminopropionic acid (β-ODAP) in its seed and leaf, which is known as the principle neurotoxin to cause neurolathyrism (a motor neurodegenerative disease of humans and animals) during prolonged consumption as regular diet. Till date, the knowledge on β-ODAP biosynthesis in Lathyrus sp. is limited only to a small part of the complex bio-chemical steps involved including a few known sulfur-containing enzymes (viz. cysteine synthase, ODAP synthase etc.). In Lathyrus sativus, biosynthesis of β-ODAP varies differentially in a tissue-specific manner as well as in response to several environmental stresses viz. zinc deficiency, iron over-exposure, moisture stress etc. In the present study, a novel cysteine synthase gene (LsCSase) from Lathyrus sativus L was identified and characterized through bioinformatics approaches. The bioinformatic analysis revealed that LsCSase showed maximum similarity with the O-acetyl serine (thiol) lyase of Medicago truncatula with respect to several significant sequence-specific conserved motifs (cysK, CBS like, ADH_zinc_N, PALP), sub-cellular localization (chloroplast or cytoplasm) etc., similar to other members of cysteine synthase protein family. Moreover, the tissue-specific regulation of the LsCSase as well as its transcriptional activation under certain previously reported stressed conditions (low Zn⁺²-high Fe⁺², PEG induced osmotic stress) were also documented through quantitative real-time PCR analyses, suggesting a possible link between the LsCSase gene activation and β-ODAP biosynthesis to manage external stresses in grass pea. This preliminary study offers a probable way towards the development of less toxic consumer-safe grass pea by down-regulation or deactivation of such gene/s (cysteine synthase) through genetic manipulations.

New insights into the mechanism of neurolathyrism: L-β-ODAP triggers [Ca2+]i accumulation and cell death in primary motor neurons through transient receptor potential channels and metabotropic glutamate receptors

Neurolathyrism is a motor neuron (MN) disease caused by β-N-oxalyl-L-α,β-diaminopropionic acid (L-β-ODAP), an AMPA receptor agonist. L-β-ODAP caused a prolonged rise of intracellular Ca(2+) ([Ca(2+)]i) in rat spinal cord MNs, and the [Ca(2+)]i accumulation was inversely proportional to the MN's life span. The [Ca(2+)]i rise induced by L-β-ODAP or (S)-AMPA was antagonized completely by NBQX, an AMPA-receptor blocker. However, blocking the L-type Ca(2+) channel with nifedipine significantly lowered [Ca(2+)]i induced by (S)-AMPA, but not that by L-β-ODAP. Tetrodotoxin completely extinguished the [Ca(2+)]i rise induced by (S)-AMPA or kainic acid, whereas that induced by L-β-ODAP was only attenuated by 65.6±6% indicating the prominent involvement of voltage-independent Ca(2+) entry. The tetrodotoxin-resistant [Ca(2+)]i induced by L-β-ODAP was blocked by 2-APB, Gd(3+), La(3+), 1-(β-[3-(4-methoxy-phenyl)propoxy]-4-methoxyphenethyl)-1H-imidazole hydrochloride (SKF-96365) and flufenamic acid, which all are blockers of the transient receptor potential (TRP) channels. Blockers of group I metabotropic glutamate receptors (mGluR I), 7-(hydroxyiminocyclopropan[b]chromen-1α-carboxylate ethyl ester (CPCCPEt) and 2-methyl-6-(phenylethynyl)-pyridine (MPEP) also lowered the [Ca(2+)]i rise by L-β-ODAP. MN cell death induced by L-β-ODAP was prolonged significantly with SKF-96365 as well as NBQX. The results show the involvement of TRPs and mGluR I in L-β-ODAP-induced MN toxicity through prolonged [Ca(2+)]i mobilization, a unique characteristic of this neurotoxin.

The contents of the neuro-excitatory amino acid β-ODAP (β-N-oxalyl-l-α,β-diaminopropionic acid), and other free and protein amino acids in the seeds of different genotypes of grass pea (Lathyrus sativus L.)

The free and protein amino acids of nine different genotypes of grass pea (Lathyrus sativus L.) seeds were analysed by HPLC with pre-column PITC (phenyl isothiocyanate) derivatisation. Among the free amino acids, homoarginine was quantitatively the most important (up to 0.8% seed weight) and stable while the neuro-excitatory amino acid β-ODAP (β-N-oxalyl-l-α,β-diaminopropionic acid) showed highest variation (0.02-0.54%) in the nine genotypes examined. Among protein amino acids, glutamic acid was quantitatively most significant, followed by aspartic acid, arginine, leucine, lysine and proline. The sulphur amino acid, methionine, showed the lowest concentration in all the L. sativus genotypes, and also in lentil (Lens culinaris) and in soybean (Glycine max) seeds analysed at the same time.