Phytomedicines and nutraceuticals: alternative therapeutics for sickle cell anemia

Antioxidant-Rich Nutraceutical as a Therapeutic Strategy for Sickle Cell Disease

Sickle cell disease (SCD) is a genetically inherited disease in which the "SS" individual possesses two copies of the abnormal beta-globin gene. This disease is one of the most dominant genetic diseases in the world. SCD is marked by the propensity of red cell hemoglobin to polymerize and distort the red cell from a biconcave disk shape into a sickle shape, resulting in a typical vaso-occlusive episode and accelerated hemolysis. Plants are rich sources of bioactive compounds that are promising anti-sickling agents to scavenge free radicals, thereby ensuring oxidative balance. The current review highlights the potential therapeutic benefits of antioxidant-rich nutraceutical in the treatment and management of sickle cell disease. The anti-sickling potential of nutraceutical is attributed to the presence of antioxidant bioactive chemicals such as alkaloids, polyphenols, vitamins, and minerals, which acts as scavengers of free radicals that prevent oxidative damage of the hemoglobin and prevent hemolysis, facilitating longer erythrocyte lifespan. The challenges of current therapies for SCD and future directions are also discussed.KEY TEACHING POINTSSickle cell disease is a genetically inherited disease in which SS individuals possess two copies of the abnormal beta-globin gene.Oxidative stress contributes to the pathophysiology of secondary dysfunction in sickle cell patients.Antioxidants can play a vital role in maintaining a balance between oxidant and antioxidant defense systems.Nutraceutical rich in antioxidants such as alkaloids, polyphenols, vitamins, and minerals is potential therapeutic agents for sickle cell disease.An antioxidant-rich nutraceutical may act to reduce vaso-occlusive crises.

Underutilized legumes, Cajanus cajan and Glycine max may bring about antisickling effect in sickle cell disease by modulation of redox homeostasis in sickled erythrocytes and alteration of its functional chemistry

The antisickling and anti-oxidative effect of the Cajanus cajan, Glycine max, and their blends were investigated in sickled erythrocytes. The powdered samples were analyzed for their nutritional and anti-nutritional constituents. Their aqueous extracts were analyzed for in vitro antioxidant activities. The extracts were incubated with sickled erythrocytes at 37°C for 6 hours and the antisickling effect examined via microscopic analysis. The blend was the most active and its incubated cells were subjected to anti-oxidative analysis which covers for GSH, SOD, catalase, and lipid peroxidation (LPO). Chemical functional group of the treated cells was analyzed with FTIR spectroscopy. The in silico binding of the predominant amino acid to hemoglobin was also investigated. An increased concentration of leucine was observed in the blend compared to that of C. cajan and G. max, respectively. Vitamins C, B6, and B9 were the only vitamins observed in the blend. Phytate and oxalate were present in all samples. All extracts displayed significant (p < .05) scavenging activities. Treatment with the blend exacerbated SOD and catalase activities as well as the GSH level, while suppressing LPO. FTIR analysis of the treated cells showed the presence of hydrophobic functional groups. Leucine was the predominant amino acid, and it showed a potent molecular interaction with HIS-87 residue of the alpha chain of 1HCO. C. cajan and G. max blend inhibited sickling activities of sickle erythrocytes, while concomitantly exacerbating their endogenous antioxidant enzymes activity and modification of the functional chemistry. PRACTICAL APPLICATIONS: Cajanus cajan and Glycine max are among the common underutilized legumes in Nigeria. Aside their nutritional properties, these legumes have been used from time immemorial for the treatment and management of various ailments. Sickle cell anemia is a class of hemoglobinopathy common in Sub-Saharan Africa. There have been concerns about its treatment owing to the increasing scourge of the disease coupled to the financial burden of its management. This study reports the ability of the potentials of the legumes to prevent sickling activities of sickled erythrocytes and the possible biochemical mechanism involved.

Functional foods: promising therapeutics for Nigerian Children with sickle cell diseases

Sickle cell disease (SCD), also known as sickle cell anemia (SCA) is one of the structural hemoglobinopathies that occurs due to a single nucleotide mutation from GAG to GTG, which changes the amino acid of a β-globin chain of hemoglobin (Hb) from glutamate to valine. This singular mutation results to disorderliness in red blood cells (RBCs) with advent of changes in RBC morphology and other pathological conditions. In the 1980s, intermittent red blood cell transfusions, opioids, and penicillin prophylaxis were the only available therapy for SCA and were commonly reserved for acute, life threatening complications. So far, the US Food and Drug Administration (FDA) has granted a total of four drugs approval for the prophylaxis and treatment of the clinical complications of SCD. Due to limitations (adherence, safety, adverse effects) of existing therapies in the prophylaxis and treatment of SCD complications in Nigerian children and their inaccessibility to approved drugs, the present study discusses the therapeutic effects of readily available functional food as one of the therapies or an adjunct therapy to tackle the sickle cell crisis in Nigerian Children.

Advances in Sickle Cell Disease Treatments

Sickle Cell Disease (SCD) is an inherited disorder of red blood cells that is caused by a single mutation in the β -globin gene. The disease, which afflicts millions of patients worldwide mainly in low income countries, is characterized by high morbidity, mortality and low life expectancy. The new pharmacological and non-pharmacological strategies for SCD is urgent in order to promote treatments able to reduce patient's suffering and improve their quality of life. Since the FDA approval of HU in 1998, there have been few advances in discovering new drugs; however, in the last three years voxelotor, crizanlizumab, and glutamine have been approved as new therapeutic alternatives. In addition, new promising compounds have been described to treat the main SCD symptoms. Herein, focusing on drug discovery, we discuss new strategies to treat SCD that have been carried out in the last ten years to discover new, safe, and effective treatments. Moreover, non-pharmacological approaches, including red blood cell exchange, gene therapy and hematopoietic stem cell transplantation will be presented.

Natural Antioxidants in Anemia Treatment

Anemia, characterized by a decrease of the hemoglobin level in the blood and a reduction in carrying capacity of oxygen, is a major public health problem which affects people of all ages. The methods used to treat anemia are blood transfusion and oral administration of iron-based supplements, but these treatments are associated with a number of side effects, such as nausea, vomiting, constipation, and stomach pain, which limit its long-term use. In addition, oral iron supplements are poorly absorbed in the intestinal tract, due to overexpression of hepcidin, a peptide hormone that plays a central role in iron homeostasis. In this review, we conducted an analysis of the literature on biologically active compounds and plant extracts used in the treatment of various types of anemia. The purpose of this review is to provide up-to-date information on the use of these compounds and plant extracts, in order to explore their therapeutic potential. The advantage of using them is that they are available from natural resources and can be used as main, alternative, or adjuvant therapies in many diseases, such as various types of anemia.

In vitro assessment of the anti-sickling properties of Buchholzia coriacea and Mucuna pruriens seed extracts

Sickle cell disease is a group of diseases inherited through the gene and it affects the haemoglobin in the red blood cell. This study investigated the methanol seed extract of Buchholzia coriacea for possible in vitro anti-sickling effects and also determined the effect of Mucuna pruriens seed extract on the solubility and oxygen-binding rate of sickle cell haemoglobin. Sickle cell blood was collected from sickle cell disease patients with subsequent addition of 2% sodium metabisulphite to cause more sickling. Varying concentrations of the seed extracts (50%, 25%, 12.5% and 6.25%) were added to the pre-treated blood for these in vitro assays. The results showed that the extract of Buchholzia coriacea significantly (P < 0.05) inhibited sickling at all concentrations with the highest percentage inhibition of 73.3 ± 5.8, reversed sickled erythrocytes at all concentrations with the highest percentage reversal of 83.3 ± 5.8 and significantly (P < 0.05) inhibited polymerisation at all concentrations used in comparison to the parallel control. The extract of Mucuna pruriens seed significantly (P < 0.05) increased the solubility of sickle haemoglobin at 50%, 25%, 12.5% and 6.25% concentrations, increased Fe^2+/Fe³⁺ ratio from 1.7 (control) to 12.2 (50% concentration) and reduced osmotic fragility (at 12.5% and 6.25% concentrations) when compared with parallel control. The results indicate the feasibility of the seed extracts as promising agents in the management of sickle cell disease.

Biochemical investigation of the upstream anti-sickling mechanisms of soursop (Annona muricata): 15-acetyl guanacone as an inhibitor of deoxyhaemoglobin polymerisation

Current sickle cell disease (SCD) therapies are limited and inefficient. The ethnomedicinal values of Annona muricata in the treatment of SCD, leading to this present research. Leaves and fruits of Annona muricata were processed using solvent extraction and partitioning; aqueous, chloroform and ethyl acetate fractions. In vitro (anti-oxidant and anti-sickling), in silico, quantitative (amino acids) and kinetic simulation experiments were done. 15-acetyl guanacone, was used, in silico against 2,3-bisphosphoglycerate (2, 3-BPG) mutase and deoxyhaemoglobin. The ethyl acetate and chloroform fractions better NO^● scavengers, iron-chelators and ferric reducing. In vitro unsickling (UT₅₀) had ethyl acetate = 5 h and methanol = 7 h. Chloroform fraction had EC₅₀ 1.00 mg/mL (EC₅₀ = 546 mg/mL) to 10.00 mg/mL (EC₅₀ = 99 mg/mL). EC₅₀ and IC₅₀ of ethyl acetate fraction had steady-decrease. At higher concentration, chloroform fraction had higher Bmax (1.48 × 10²¹ U/mL) and higher Kd (3.66 × 10¹⁹ mg/mL), whereas, at a lower concentration, the ethyl acetate fraction demonstrated higher Bmax (7.23 × 10¹² U/mL) and lower Kd (2.12 × 10¹¹ mg/mL); The relative affinity (BP) of chloroform fraction increased progressively with concentration. The amino acid profile revealed rich concentrations glycine, valine, leucine, lysine, phenylalanine, histidine, arginine, and tryptophan. From the in silico experiments, 15-acetyl guanacone specifically targeted the A and B chains, with greater affinity for the beta subunit. This suggested that 15-acetyl guanacone might be able to prevent the polymerisation of deoxyHbSS, induce an allosteric conformational change that increases the oxygen affinity, and decrease the cellular 2, 3-BPG concentration.Communicated by Ramaswamy H. Sarma.

Phytomedicines (medicines derived from plants) for sickle cell disease

BACKGROUND

Sickle cell disease, a common recessively inherited haemoglobin disorder, affects people from sub-Saharan Africa, the Middle East, Mediterranean basin, Indian subcontinent, Caribbean and South America. It is associated with complications and a reduced life expectancy. Phytomedicines (medicine derived from plants in their original state) encompass many of the plant remedies from traditional healers which the populations most affected would encounter. Laboratory research and limited clinical trials have suggested positive effects of phytomedicines both in vivo and in vitro. However, there has been little systematic appraisal of their benefits. This is an updated version of a previously published Cochrane Review.

OBJECTIVES

To assess the benefits and risks of phytomedicines in people with sickle cell disease of all types, of any age, in any setting.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register, the International Standard Randomised Controlled Trial Number Register (ISRCTN), the Allied and Complimentary Medicine Database (AMED), ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). Dates of most recent searches: Cochrane Cystic Fibrosis and Genetic Disorders Haemoglobinopathies Trials Register: 17 March 2020; ISRCTN: 19 April 2020; AMED: 18 May 2020; ClinicalTrials.gov: 24 April 2020; and the WHO ICTRP: 27 July 2017.

SELECTION CRITERIA

Randomised or quasi-randomised trials with participants of all ages with sickle cell disease, in all settings, comparing the administration of phytomedicines, by any mode to placebo or conventional treatment, including blood transfusion and hydroxyurea.

DATA COLLECTION AND ANALYSIS

Both authors independently assessed trial quality and extracted data.

MAIN RESULTS

Three trials (212 participants) of three phytomedicines: Niprisan^® (also known as Nicosan^®), Ciklavit^® and a powdered extract of Pfaffia paniculata were included. The Phase IIB (pivotal) trial suggests that Niprisan^® may be effective in reducing episodes of severe painful sickle cell disease crisis over a six-month period (low-quality evidence). It did not appear to affect the risk of severe complications or the level of anaemia (low-quality evidence). The single trial of Cajanus cajan (Ciklavit^®) reported a possible benefit to individuals with painful crises, and a possible adverse effect (non-significant) on the level of anaemia (low-quality evidence). We are uncertain of the effect of Pfaffia paniculata on the laboratory parameters and symptoms of SCD (very low-quality of evidence). No adverse effects were reported with Niprisan^® and Pfaffia paniculata (low- to very low-quality evidence).

AUTHORS' CONCLUSIONS

While Niprisan^® appeared to be safe and effective in reducing severe painful crises over a six-month follow-up period, further trials are required to assess its role in managing people with SCD and the results of its multicentre trials are awaited. Currently, no conclusions can be made regarding the efficacy of Ciklavit^® and the powdered root extract of Pfaffia paniculata in managing SCD. Based on the published results for Niprisan^® and in view of the limitations in data collection and analysis of the three trials, phytomedicines may have a potential beneficial effect in reducing painful crises in SCD. This needs to be further validated in future trials. More trials with improved study design and data collection are required on the safety and efficacy of phytomedicines used in managing SCD.

Phytocomponents from Anacardium occidentale, Psidium guajava, and Terminalia catappa altered membrane osmotic stability of sickle erythrocytes

Background

The present study identified, quantified, and characterized the combinations of phytocomponents from fractionated leaf extracts of Anacardium occidentale, Psidium guajava, and Terminalia catappa that stabilized sickle erythrocyte membrane against osmotic stress, or otherwise, using standard chromatographic-spectrophotometric techniques, namely GC-MS, FT-IR, and UV-visible systems.

Results

The percentage hemolysis of the control sample, in 0.9 g/100 mL NaCl, was 35.08 ± 11.64%, whereas those of the samples containing 40 mg/100 mL, 60 mg/100 mL, and 80 mg/100 mL of ethylacetate extracts of T. catappa ranged between 31.82 ± 8.32 and 39.18 ± 6.94%. Ethylacetate extract of T. catappa contained comparative high quantities of hexadecanoic acid methyl ester, 9,11-octadecadienoic acid, methyl ester, (E, E)-, trans-13-octadecenoic acid methyl ester, and methyl stearate. FT-IR and UV-visible spectra showed that ethylacetate extract of T. catappa contained aromatic compounds as well as nitro-compounds, phenolics, and esters.

Conclusion

To mention but a few, the combinations of major phytocomponents that stabilized sickle erythrocyte membrane against osmotic stress were hexadecanoic acid, methyl ester, 11-octadecenoic acid, methyl ester, dibutyl phthalate, pentacosane, trans-13-octadecenoic acid, methyl ester, whereas the minor phytocomponents include methyl tetradecanoate, methoxyacetic acid, 3-pentadecyl ester, methyl stearate, hexadecanoic acid, isoxazole, 4,5-dimethyl-.

Sickling-suppressive effects of chrysin may be associated with sequestration of deoxy-haemoglobin, 2,3-bisphosphoglycerate mutase, alteration of redox homeostasis and functional chemistry of sickle erythrocytes

Sickle cell disease (SCD) is a medical condition caused by mutation in a single nucleotide in the β-globin gene. It is a health problem for people in sub-Saharan Africa, the Middle East and India. Orthodox drugs developed so far for SCD focus largely on symptomatic respite of pain and crisis mitigation. We investigated the antisickling effects of chrysin via modulation of deoxy-haemoglobin, 2,3-bisphosphoglycerate mutase, redox homeostasis and alteration of functional chemistry in human sickle erythrocytes. In silico and in vitro methods were adopted for the studies. Chrysin was docked against deoxy-haemoglobin and 2,3-bisphosphoglycerate mutase, with binding energies (-24.064 and -18.171 kcal/mol) and inhibition constant (K _i) of 0.990 µM and 0.993 µM at their active sites through strong hydrophobic and hydrogen bond interactions. Sickling was induced with 2% metabisulphite at 3 h. Chrysin was able to prevent sickling maximally at 2.5 µg/mL and reversed the same at 12.5 µg/mL, by 66.5% and 69.6%, respectively. Treatment with chrysin significantly (p < 0.05) re-established the integrity of erythrocytes membrane as evident from the observed percentage of haemolysis relative to induced erythrocytes. Chrysin also significantly (p < 0.05) prevented and reversed lipid peroxidation. Similarly, glutathione and catalase levels were observed to significantly (p < 0.05) increase with concomitant significant (p < 0.05) decrease in superoxide dismutase activity relative to untreated. From Fourier-transform infrared results, treatment with chrysin was able to favourably alter the functional chemistry, judging from the shifts and functional groups observed. Sickling-suppressive effects of chrysin may therefore be associated with sequestration of deoxy-haemoglobin, 2,3-bisphosphoglycerate mutase, alteration of redox homeostasis and functional chemistry of sickle erythrocytes.

Inhibitory and Reversal Effects of Extracts and Fractions of Anogeissus leiocarpa (DC.) Guill. & Perr. on Sodium Metabisulphite– induced Polymerization of Sickle Cell Haemoglobin

Background:

The leaves and stem bark of Anogeissus leiocarpa (DC.) Guill. & Pirr. (Combretaceae) are commonly included in recipes used for the management of sickle cell disease in western part of Nigeria.

Objective:

The present study was carried out to evaluate the potential of methanol extract and various fractions of A. leiocarpa leaves and stem bark to inhibit as well as reverse sodium metabisulphite induced polymerization of sickle cell haemoglobin.

Method:

The modified Emmel test was used to evaluate the inhibitory activity and the reversal effects of the extracts and fractions of both the leaves and the stem bark of A. leiocarpa in vitro.

Results:

Both the leaves and the stem bark extracts of A. leiocarpa were effective at inhibiting as well as reversing sodium metabisulphite induced polymerization of sickle cell haemoglobin, though the activity was higher in the leaves (94.52 ± 0.80% and 95.67 ± 0.67% respectively) when compared with the stem bark (51.79 ± 2.46 % and 50.45 ± 3.18 % respectively). The ethyl acetate fraction of both leaves and stem bark also gave good activities in both test methods with percentage reversal of 82.74 ± 1.82% and 67.63 ± 2.18% respectively.

Conclusions:

: A. leiocarpa extracts and ethyl acetate fractions exhibit good inhibition and reversal of sodium metabisulphite–induced polymerization of sickle cell haemoglobin thus justifying its inclusion in remedies used for the traditional management of sickle cell.

Antisickling Effects of Quercetin may be Associated with Modulation of Deoxyhaemoglobin, 2, 3-bisphosphoglycerate mutase, Redox Homeostasis and Alteration of Functional Chemistry in Human Sickle Erythrocytes

It is now glaring that sickle cell anaemia is still one of the highest leading inbred hemoglobinopathy amongst Africans. This study examined the antisickling effects of quercetin via modulation of deoxy-haemoglobin, redox homeostasis and alteration of functional chemistry in human sickle erythrocyte using in silico and in vitro models while espousing preventive and curative approaches. Quercetin was docked against deoxy-haemoglobin and 2, 3-bisphosphoglycerate mutase, with binding energies (−30.427 and −21.106 kcal/mol) and Ki of 0.988μM and 0.992μM at their catalytic sites via strong hydrophobic and hydrogen bond interactions. Induction of sickling was done using 2% metabisulphite at 3h. Treatment with quercetin prevented sickling outstandingly at 5.0μg/mL and reversed same at 7.5μg/mL, 83.6% and 75.9%, respectively. Quercetin also significantly (P<0.05) maintained the integrity of erythrocyte membrane apparently from the observed % haemolysis relative to untreated. Quercetin significantly (P<0.05) prevented and counteracted lipid peroxidation while stimulating GSH and CAT levels which were detected to considerably (P<0.05) increase with simultaneous significant (P<0.05) reduction in SOD level based on curative approach. Umpiring from our FTIR results, a favorable alteration in the part of functional chemistry in terms of shifts (bend and stretches) and functional groups were observed relative to the induced erythrocyte/untreated. Thus, antisickling effects of quercetin may be associated with modulation of deoxy-haemoglobin, redox homeostasis and alteration of functional chemistry in human sickle erythrocytes.

Sickling-preventive effects of rutin is associated with modulation of deoxygenated haemoglobin, 2,3-bisphosphoglycerate mutase, redox status and alteration of functional chemistry in sickle erythrocytes

Sickle cell anaemia is a hereditary disease branded by an upsurge in generation of ROS, irregular iron release and little or no antioxidant activity which can lead to cellular injuries due to oxidative stress resulting in severe symptoms including anaemia and pain. The disease is caused by a mutated version of the gene that helps make haemoglobin, the protein that carries oxygen in red blood cells. We used in silico and in vitro experiments to examine the antisickling effects of rutin for the first time by means of before and after induction approaches in sickle erythrocytes. Rutin was docked against deoxy-haemoglobin and 2,3-bisphosphoglycerate mutase, revealing binding energies (-27.329 and -25.614 kcal/mol) and Ki of 0.989μM and 0.990 μM at their catalytic sites through strong hydrophobic and hydrogen bond interactions. Sickling was thereafter, induced at 3 h with 2% metabisulphite. Rutin prevented sickling maximally at 12.3μM and reversed same at 16.4μM, by 78.5% and 69.9%, one-to-one. Treatment with rutin significantly (P < 0.05) reinvented the integrity of erythrocytes membrane as evident from the practical % haemolysis compared to induced erythrocytes. Rutin also significantly (P < 0.05) prevented and reversed lipid peroxidation relative to untreated. Likewise, GSH, CAT levels were observed to significantly (P < 0.05) increase with concomitant significant (P < 0.05) decrease in SOD activity based on administration of rutin after sickling induction approach. Furthermore, FTIR results showed that treatment with rutin favourably altered the functional chemistry, umpiring from shifts and functional groups observed. It can thus be deduced that, antisickling effects of rutin may be associated with modulation of deoxy-haemoglobin, 2,3-bisphosphoglycerate mutase, alteration of redox homeostasis and functional chemistry of sickle erythrocytes.

Herbal Drug use in Sickle Cell Disease Management; Trends and Perspectives in Sub-Saharan Africa - A Systematic Review

INTRODUCTION

Nigeria has the largest burden of Sickle Cell Disease (SCD) with estimated 100,000 new born affected annually. SCD is a Hemoglobin (Hb) disorder with the major form resulting from the substitution of a polar glutamate (Glu) by non-polar Valine (Val) in an invariant region of Hbβ chain-subunit. Species of Hb found in the sickle cell trait are HbA and HbS in a 60:40 proportion, in SCD only HbS, in the HbC disease only HbC, and in the SC disease it's HbS and HbC in a 50:50 equal proportion.

OBJECTIVE

This paper reviews herbal medicines usage in sub-Saharan Africa (sSA) to ameliorate the crisis associated with SCD. The model Hb tetramer suggests a higher membrane affinity of HbS and HbC, promoting dehydration of RBCs, with concomitant in vivo crystallization. Some drawbacks using these herbal drugs include; poor bioavailability and the lack of proper pharmacovigilance monitoring procedures arising from weak governance structure combined with under reporting of herbal usage to physicians were discussed. Probable epigenetic loci that could be targeted using phytomedicines for effective SCD management were also discussed.

METHODS

Using search engines, several databases including Google scholar, PubMed, Academic Resource Index were utilized as a source for relevant publications/ literature. The protein coordinates for the Hb tetramer were obtained from the Protein Data Bank (PDB).

CONCLUSION

Manipulation of epigenetics to achieve better SCD management involves careful thinking. Herein, we discuss some epigenetic interactions that could be putatively tweaked with a view of enhancing soluble bioactive small molecular components with the potential to reactivate γ -globin genes, thereby boosting immune response in patient with SCD.

Phytomedicines (medicines derived from plants) for sickle cell disease

BACKGROUND

Sickle cell disease, a common recessively inherited haemoglobin disorder, affects people from sub-Saharan Africa, the Middle East, Mediterranean basin, Indian subcontinent, Caribbean and South America. It is associated with complications and a reduced life expectancy. Phytomedicines (medicine derived from plants in their original state) encompass many of the plant remedies from traditional healers which the populations most affected would encounter. Laboratory research and limited clinical trials have suggested positive effects of phytomedicines both in vivo and in vitro. However, there has been little systematic appraisal of their benefits. This is an update of a Cochrane Review first published in 2004, and updated in 2010, 2013, and 2015.

OBJECTIVES

To assess the benefits and risks of phytomedicines in people with sickle cell disease of all types, of any age, in any setting.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Haemoglobinopathies Trials Register, the International Standard Randomised Controlled Trial Number Register (ISRCTN), the Allied and Complimentary Medicine Database (AMED), ClinicalTrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP).Dates of most recent searches: Cochrane Cystic Fibrosis and Genetic Disorders Haemoglobinopathies Trials Register: 10 April 2017; ISRCTN: 26 July 2017; AMED: 24 August 2017; ClinicalTrials.gov: 02 August 2017; and the WHO ICTRP: 27 July 2017.

SELECTION CRITERIA

Randomised or quasi-randomised trials with participants of all ages with sickle cell disease, in all settings, comparing the administration of phytomedicines, by any mode to placebo or conventional treatment, including blood transfusion and hydroxyurea.

DATA COLLECTION AND ANALYSIS

Both authors independently assessed trial quality and extracted data.

MAIN RESULTS

Two trials (182 participants) and two phytomedicines Niprisan^® (also known as Nicosan^®) and Ciklavit^® were included. The Phase IIB (pivotal) trial suggests that Niprisan^® was effective in reducing episodes of severe painful sickle cell disease crisis over a six-month period (low-quality evidence). It did not affect the risk of severe complications or the level of anaemia (low-quality evidence). No serious adverse effects were reported. The single trial of Cajanus cajan (Ciklavit^®) reported a possible benefit to individuals with painful crises (low-quality evidence), and a possible adverse effect (non-significant) on the level of anaemia (low-quality evidence).

AUTHORS' CONCLUSIONS

While Niprisan^® appeared to be safe and effective in reducing severe painful crises over a six-month follow-up period, further trials are required to assess its role in the management of people with sickle cell disease and the results of its multicentre trials are awaited. Currently no conclusions can be made regarding the efficacy of Ciklavit^®. Based on the published results for Niprisan^® and in view of the limitations in data collection and analysis of both trials, phytomedicines may have a potential beneficial effect in reducing painful crises in sickle cell disease. This needs to be further validated in future trials. More trials are required on the safety and efficacy of phytomedicines used in managing sickle cell disease.

Deleterious Effects of Chronic Folate Deficiency in the Ts65Dn Mouse Model of Down Syndrome

Folate is an important B vitamin naturally found in the human diet and plays a critical role in methylation of nucleic acids. Indeed, abnormalities in this major epigenetic mechanism play a pivotal role in the pathogenesis of cognitive deficit and intellectual disability in humans. The most common cause of cognitive dysfunction in children is Down syndrome (DS). Since folate deficiency is very common among the pediatric population, we questioned whether chronic folate deficiency (CFD) exacerbates cognitive dysfunction in a mouse model of DS. To test this, adult Ts65Dn mice and their disomic littermates were chronically fed a diet free of folic acid while preventing endogenous production of folate in the digestive tract for a period of 8 weeks. Our results show that the Ts65Dn mouse model of DS was significantly more vulnerable to CFD in terms of plasma homocysteine and N5-methyltetrahydrofolate (5-MTHF) levels. Importantly, these changes were linked to degenerative alterations in hippocampal dendritic morphology and impaired nest building behavior in Ts65Dn mice. Based on our results, a rigorous examination of folate intake and its metabolism in individuals with DS is warranted.

Monodora myristica (African nutmeg) modulates redox homeostasis and alters functional chemistry in sickled erythrocytes

The antioxidative effect of Monodora myristica seed acetone extract and its effect on chemical functional groups were investigated in sickled erythrocytes as well as molecular modeling of the antisickling potentials of its secondary metabolites. The extract was subjected to gas chromatography–mass spectrometry to identify the compounds present, which were then docked into the allosteric-binding site of deoxy-hemoglobin. The extract was incubated with sickled erythrocytes at 37°C for 6, 12, and 24 h and were subjected to antioxidative analysis for reduced glutathione (GSH), superoxide dismutase (SOD), catalase, and lipid peroxidation (LPO). Chemical functional group of the treated cells was analyzed via Fourier transform infrared spectroscopy (FTIR). The predominant compounds identified were 17-octadecynoic acid; oleic acid, androstan-3-one, 17-hydroxy-2-methyl- (2.beta.,5.beta.,17.beta.)-; estran-3-one, 17-(acetyloxy)-2-methyl-, (2.alpha., 5.alpha., 17.beta.), and (+)-3-carene, 10-(acetylmethyl)-. They all fitted well within the active site of Hb with good binding affinity, as evidenced by the negative CDocker interaction energies of their complexes ranging between −54.4 and −26.7 kcal/mol. Treatment with the extract exacerbated SOD and catalase activities as well as GSH level, while LPO was suppressed. This antioxidative activity was time and/or dose dependent, with 6 and 12 h incubation showing the optimum activity. FTIR analysis of the treated cells showed the presence of hydrophobic functional groups. The synergetic molecular interaction of the major compounds of the extract with the α-dimer of Hb depicts an antisickling effect of M. myristica acetone extract. This is accompanied by exacerbation of endogenous antioxidant enzymes activity and modification of the functional chemistry of the cells.

Antidiabetic Properties, Bioactive Constituents, and Other Therapeutic Effects of Scoparia dulcis

This review discusses the antidiabetic activities of Scoparia dulcis as well as its antioxidant and anti-inflammatory properties in relation to the diabetes and its complications. Ethnomedical applications of the herb have been identified as treatment for jaundice, stomach problems, skin disease, fever, and kidney stones, reproductory issues, and piles. Evidence has been demonstrated through scientific studies as to the antidiabetic effects of crude extracts of S. dulcis as well as its bioactive constituents. The primary mechanisms of action of antidiabetic activity of the plant and its bioactive constituents are through α-glucosidase inhibition, curbing of PPAR-γ and increased secretion of insulin. Scoparic acid A, scoparic acid D, scutellarein, apigenin, luteolin, coixol, and glutinol are some of the compounds which have been identified as responsible for these mechanisms of action. S. dulcis has also been shown to exhibit analgesic, antimalarial, hepatoprotective, sedative, hypnotic, antiulcer, antisickling, and antimicrobial activities. Given this evidence, it may be concluded that S. dulcis could be promoted among the masses as an alternative and complementary therapy for diabetes, provided further scientific studies on the toxicological and pharmacological aspects are carried out through either in vivo or clinical means.

Precipitating factors and targeted therapies in combating the perils of sickle cell disease--- A special nutritional consideration

Nutritional research in sickle cell disease has been the focus in recent times owing to not only specific nutritional deficiencies, but also the improvements associated with less painful episodes. Though hydroxyurea remains the drug of choice, certain adverse health effects on long term supplementation makes room for researches of different compounds. Macro and micro nutrient deficiencies, along with vitamins, play an important role in not only meeting the calorific needs, but also reducing clinical complications and growth abnormalities. Symptoms of hyper protein metabolism, increased cell turnover, increased cardiac output, and appetite suppression due to enhanced cytokine production, might give us leads for better understanding of the mechanisms involved. Different nutritional approaches comprising of traditional herbal therapies, antioxidants, flavonoids, vitamins, minerals etc., reducing oxidative stress and blood aggregation, have been tried out to increase the health potential. Nutritional therapies may also serve complementary to the newer therapies using ozone, hematopoietic stem cell transplantation, antifungal medications, erythropoietin etc. Herein we try to present a holistic picture of the different patho-physiological mechanisms, and nutritional strategies adopted.

Ethnomedicinal survey of medicinal plants used in the management of sickle cell disorder in Southern Nigeria

ETHNOPHARMACOLOGICAL RELEVANCE

The present study entails the medicinal plant species used to manage sickle cell disorder in Southern States of Nigeria.

MATERIALS AND METHODS

The ethnomedicinal information was gathered through multistage approach from three geopolitical zones of Southern Nigeria, which were purposively selected. Semi-structured questionnaires were administered on 500 respondents in 125 locations. The ethnomedicinal data collected were analyzed using quantitative value indices such as fidelity level (percentage) and use value. The information got was cross checked using literature search and other related materials.

RESULT

Five hundred respondents comprising 53.12% females and 46.88% males were observed. It was noted that 26.70% were illiterate while 73.30% had formal education. Seventy-nine percent is traditional healers, 27% herb traders and the other 4% are those who have awareness of sickle cell disease . One hundred and seventy five plant species belonging to 70 families, of which Fabaceae made up 26.76% and Euphorbiaceae 16.90% forming the highest occurrence. It was observed that leaves were the most common plant part used (69.10%) followed by root (15%) and stem bark (14%) in the preparation for sickle cell management. Majority (48.57%) of these plants were harvested from wild with 38.86% being trees. Citrus aurantifolia and Newbouldia laevis had highest use values of 0.69 and 0.64 respectively. Plants with the least use value (0.001) include Abrus canescens, Acacia xanthophloea, Aerva lanata and Axonopus compressus. The result of fidelity level values of the plant species for the management of Sickle Cell Disorder (SCD) revealed that Citrus aurantifolia had the highest value of 70.2% while Angraecum distichum and Axonopus compressus had the lowest Fidelity Level value of 0.18%.

CONCLUSION

The study revealed that people in the studied areas were well grounded in the medicinal plants used to manage sickle cell disease. This study reported for the first time 102 plant species having anti-sickling potentials with Fabaceae and Euphorbiaceae as the most dominant plant families. Many of the claimed plants were harvested from the wild showing threat thus providing needs for conservation of plants. The documented plants had high use value and fidelity level that provided quantitative and qualitative ethnomedicinal evaluation within and across the plant families. These give room for further scientific investigations in pharmacological profiles.

Antisickling and toxicological evaluation of the leaves of Scoparia dulcis Linn (Scrophulariaceae)

BACKGROUND

Scoparia dulcis Linn (Scrophulariaceae) together with other medicinal plants serve as antisickling remedies in Africa. This study was aimed at investigating the antisickling activity of the leaves of the plant as well as establishing the toxicological profile.

METHOD

Chemical tests were employed in phytochemical investigations. Evaluation of the antisickling activity involved the inhibition of sodium metabisulphite-induced sickling of the HbSS red blood cells obtained from confirmed sickle cell patients who were not in crises. Concentrations of the crude extract and its fractions were tested with normal saline and p-hydroxybenzoic acid serving as controls. Acute toxicological evaluation was carried out in mice while 30-day assessment was done in rats.

RESULTS

Phytochemical screening revealed the presence of alkaloids, tannins, flavonoids and saponins. Percentage sickling inhibitions of the aqueous methanol extracts of S. dulcis were significant all through the period of assay p < 0. 05 compared to normal saline, but not significant with PHBA. The fractions had less activity compared to the crude extracts. The LD 50 of the extract in mice was above 8000 mg/kg body weight when administered orally. Toxicological evaluations at 250 and 500 mg/kg showed mild congestion in virtually all the target organs.

CONCLUSION

The antisickling results confirmed traditional usage of Scoparia dulcis in the management of Sickle cell disorders and a candidate for further investigations.

Potential utility of melatonin as an antioxidant therapy in the management of sickle cell anemia

This study aimed to assess antioxidant effects of melatonin treatment compared to N-acetylcysteine (NAC) and to their combination in a sickle cell suspension. Sickle erythrocytes were suspended in phosphate-buffered saline, pH 7.4, composing external control group. They were also suspended and incubated at 37°C either in the absence (experimental control group) or in the presence of NAC, melatonin and their combination at concentrations of 100 pm, 100 nm and 100 μm for 1 hr (treatment groups). The melatonin influences were evaluated by spectrophotometric [hemolysis degree, catalase (CAT), glutathione S-transferase (GST), glutathione peroxidase (GPx), glutathione reductase (GR), glucose-6-phosphate dehydrogenase (G6PDH), and superoxide dismutase (SOD) activities] and chromatographic methods [glutathione (GSH) and malondialdehyde (MDA) levels]. Incubation period was able to cause a rise about 64% on hemolysis degree as well as practically doubled the lipid peroxidation levels (P < 0.01). However, almost all antioxidants tested treatments neutralized this incubation effect observed in MDA levels. Among the antioxidant biomarkers evaluated, we observed a modulating effect of combined treatment on GPx and SOD activities (P < 0.01), which showed ~25% decrease in their activities. In addition, we found an antioxidant dose-dependent effect for melatonin on lipid peroxidation (r = -0.29; P = 0.03) and for combined antioxidant treatments also on MDA levels (r = -0.37; P = 0.01) and on SOD activity (r = -0.54; P < 0.01). Hence, these findings contribute with important insight that melatonin individually or in combination with NAC may be useful for sickle cell anemia management.