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Mohammad A Alfhili,1 Jawaher Alsughayyir,2 Ahmed M Basudan,1 Hazem K Ghneim,1 Mohammed Alfaifi,3 Hassan S Alamri,4 Zuhier A Awan,5,6 Mohammed R Algethami7 1Chair of Medical and Molecular Genetics Research, Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia; 2Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia; 3Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Khalid University, Abha, Saudi Arabia; 4Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud Bin Abdulaziz University for Health Sciences (KSAU-HS), King Abdullah International Medical Research Center (KAIMRC), Riyadh, Saudi Arabia; 5Department of Clinical Biochemistry, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia; 6Department of Clinical Pathology, Al-Borg Medical Laboratories, Jeddah, Saudi Arabia; 7Ministry of Health, Jeddah, Saudi ArabiaCorrespondence: Mohammad A Alfhili, Chair of Medical and Molecular Genetics Research, Department of Clinical Laboratory Sciences, College of Applied Medical Sciences, King Saud University, Riyadh, Saudi Arabia, Tel +966-504-262-597, Email malfeehily@ksu.edu.saBackground: Risk factors of cardiovascular disease include dyslipidemia, hypertension (HTN), and anemia. Our objective is to assess the patterns of dyslipidemia in the anemic and non-anemic hypertensive Saudi population.Methods: A retrospective, cross-sectional study of the gender, blood pressure, lipid markers, and CBC parameters of 3111 subjects, which were retrieved from the database of Al-Borg Medical Laboratories over a six-year period (2014– 2019), was carried out. Means were compared among study groups and the prevalence, association, and diagnostic accuracy of lipid markers for HTN were evaluated.Results: TG, LDL/HDL, and TG/HDL were significantly higher (P < 0.0001) in hypertensives. Anemia reduces TC and LDL (P < 0.0001) in both genders, and reduces all markers and increases HDL (P < 0.01) in male hypertensives. HTN was more prevalent in anemics with high TC than normal TC (38.23% vs 11.17%, P < 0.001) and in non-anemics with high TG than normal TG (56.31% vs 21.22%, P < 0.001). Furthermore, non-anemics with high TG/HDL had the highest risk for HTN (RR = 1.20, 95% CI = 1.1551– 1.2473, P < 0.0001). Elevated TC (P = 0.0142), TG (P < 0.0001), TC/HDL (P < 0.0001), LDL/HDL (P < 0.0001), and TG/HDL (P < 0.0001), and low HDL (P < 0.0001) were risk factors for HTN as shown by ORs. In anemics, high TC/HDL, LDL/HDL, and TG/HDL were not. Importantly, only TG and TG/HDL had a discriminating capacity for HTN.Conclusion: The anemic state of hypertensive Saudi patients influences dyslipidemia which warrants further investigation.Keywords: hypertension, dyslipidemia, anemia, prevalence, Saudi Arabia

Since its introduction a decade ago, non-invasive prenatal testing (NIPT) has been recognized as a highly accurate and safe screening option for expecting mothers, with its efficacy hinging on awareness, perceptions, and understanding of the test. We surveyed pregnant women in Saudi Arabia between December 2023 and February 2024 to assess the knowledge and acceptability of NIPT among them. A total of 212 pregnant women from various risk levels, socioeconomic statuses, and trimesters participated in the study, which was carried out at King Saud University Medical City (KSUMC) via online forms. This study investigated factors affecting attitudes towards NIPT, including financial burden. Data were analyzed with descriptive statistics and chi-square tests to assess correlations. The survey revealed a significant lack of awareness about NIPT, with 64.6 % of participants unfamiliar with the test and 93.3 % answering knowledge-related questions incorrectly. Although 74.1 % were willing to undergo NIPT if it were free, only 30 % were willing to pay 1500 SAR (400 USD). These findings underscore the need for targeted knowledge translation efforts to enhance awareness and understanding of NIPT among pregnant women, highlighting the importance of addressing financial barriers and increasing educational outreach. Further research and interventions are needed to promote the uptake of NIPT and enhance the quality of antenatal care programs in Saudi Arabia., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Introduction: Protein kinases (PKs) play key roles in cellular signaling and regulation cascades and therefore are listed among the most investigated enzymes with the intent to develop drugs that are able to modulate their catalytic features. Specifically, PKs are involved in chronic diseases of large impact in the society such as cancers and neurodegeneration. Since the approval of Fasudil for the management of cerebral vasospasm, frantic efforts are currently ongoing for the development of selective PK-modulating agents., Areas Covered: A selection of the most relevant patents in the European Patent Office for biomedical innovation and/or industrial development covering the years 2020-2023 on PK modulators either of the antibody and small-molecule type is reported. In addition to the examined patents, we also reported the contributions claiming the use of antibody-targeted PKs for lab bench identification kits., Expert Opinion: The field of PK modulators for biomedical purposes is particularly crowded with contributions, making it rich in valuable information for the development of potential drugs. An emerging frontier is represented by PK activators that aims to complement the use of PK inhibitors with the final intent of finely adjusting any PK-related disruption responsible for triggering any disease.

Introduction: Epilepsy is a chronic brain disease characterized by repeated seizures and caused by excessive glutamate receptor activation. Many plants are traditionally used in the treatment of this disease. This study aimed to evaluate the bioavailability of a polyphenolic extract obtained from Origanum majorana L. (OMP) leaves, as well as its antiepileptic activity and its potential mechanism of action. Methods: We have developed and validated a simple, rapid, and accurate stability-indicating reversed-phase liquid chromatographic method for the simultaneous determination of caffeine and quercetin in rat plasma. The OMP antiepileptic effect was evaluated with pilocarpine-induced seizures, and a docking method was used to determine the possible interaction between caffeic acid and quercetin with the N-methyl-D-aspartate (NMDA) receptor. Results and Discussion: Both compounds tested showed low bioavailability in unchanged form. However, the tested extract showed an anticonvulsant effect due to the considerably delayed onset of seizures in the pilocarpine model at a dose of 100 mg/kg. The molecular docking proved a high-affinity interaction between the caffeic acid and quercetin with the NMDA receptor. Taken together, OLP polyphenols demonstrated good antiepileptic activity, probably due to the interaction of quercetin, caffeic acid, or their metabolites with the NMDA receptor., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Amaghnouje, Chebaibi, Aldossari, Ghneim, Amrati, Es-Safi, Di Cristo, Calarco, Achour, Carta, Al-Sheikh, Aboul-Soud and Bousta.)

Unpredictable chronic mild stress (UCMS) leads to variable metabolic effects. Oxidative stress (OS) of adipose tissue (AT) and mitochondrial energy homeostasis is little investigated. This work studied the effects of UCMS on OS and the antioxidant/redox status in AT and mitochondrial energy homeostasis in rats. Twenty-four male Wistar rats (180-220 g) were divided into two equal groups; the normal control (NC) group and the UCMS group which were exposed to various stresses for 28 days. An indirect calorimetry machine was used to measure volumes of respiratory gases (VO 2 & VCO 2 ), total energy expenditure (TEE), and food intake (FI). The AT depots were collected, weighed, and used for measuring activities and gene expression of key antioxidant enzymes (GPx1, SOD, CAT, GR, GCL, and GS), OS marker levels including superoxide anion (SA), peroxynitrite radical (PON), nitric oxide (NO), hydrogen peroxide (H 2 O 2 ), lipid peroxides (LPO), t-protein carbonyl content (PCC), and reduced/oxidized glutathione levels (GSH, GSSG). Additionally, AT mitochondrial fractions were used to determine the activities of the tricarboxylic acid cycle (TCA) cycle enzymes (CS, α-KGDH, ICDH, SDH, MDH), respiratory chain complexes I-III, II-III, IV, the nicotinamide coenzymes NAD + , NADH, and ATP/ADP levels. Compared with the NC group, the UCMS group showed very significantly increased OS marker levels, lowered antioxidant enzyme activities and gene expression, as well as lowered TCA cycle and respiratory chain activity and NAD + , NADH, and ATP levels (p < .001 for all comparisons). Besides, the UCMS group had lowered TEE and insignificant FI and weight gain. In conclusion, AT of the UCMS-subjected rats showed a state of disturbed redox balance linked to disrupted energy homeostasis producing augmentation of AT., (© 2023 John Wiley & Sons Ltd.)

Background and Objectives : Obesity is a chronic inflammatory condition and is considered a major risk factor for cardiovascular disease (CVD). The effects of obesity management via sleeve gastrectomy (SG) and lifestyle intervention (LS) on inflammatory cytokines, redox status, and CVD risk were studied in this work. Materials and Methods : A total of 92 participants (18 to 60 years old) with obesity (BMI ≥ 35 kg/m 2 were divided into two groups: the bariatric surgery (BS) group ( n = 30), and the LS group ( n = 62). According to the achievement of 7% weight loss after 6 months, the participants were allocated to either the BS group, the weight loss (WL) group, or the weight resistance (WR) group. Assessments were performed for body composition (by bioelectric impedance), inflammatory markers (by ELISA kits), oxidative stress (OS), antioxidants (by spectrophotometry), and CVD risk (by the Framingham risk score (FRS) and lifetime atherosclerotic cardiovascular disease risk (ASCVD)). Measurements were taken before and after six months of either SG or LS (500 kcal deficit balanced diet, physical activity, and behavioral modification). Results : At the final assessment, only 18 participants in the BS group, 14 participants in the WL group, and 24 participants in the WR group remained. The loss in fat mass (FM) and weight loss were greatest in the BS group ( p < 0.0001). Levels of IL-6, TNF-a, MCP-1, CRP, and OS indicators were significantly reduced in the BS and WL groups. The WR group had significant change only in MCP-1 and CRP. Significant reductions in the CVD risk in the WL and BS groups were detected only when using FRS rather than ASCVD. The FM loss correlated inversely with FRS-BMI and ASCVD in the BS group, whereas in the WL group, FM loss correlated only with ASCVD. Conclusions : BS produced superior weight and fat mass loss. However, both BS and LS produced a similar reduction in the inflammatory cytokines, relief of OS indicators, and enhancement of antioxidant capacity, and consequently reduced the CVD risk.

Humans exploit heavy metals for various industrial and economic reasons. Although some heavy metals are essential for normal physiology, others such as Tellurium (Te), Thallium (TI), antimony (Sb), and Osmium (Os) are highly toxic and can lead to Polycystic Ovarian Syndrome (PCOS), a common female factor of infertility. The current study was undertaken to determine levels of the heavy metals TI, Te, Sb and Os in serum of PCOS females ( n = 50) compared to healthy non-PCOS controls ( n = 56), and to relate such levels with Total Antioxidant Capacity (TAC), activity of key antioxidant enzymes, oxidative stress marker levels and redox status. PCOS serum samples demonstrated significantly higher levels of TI, Te, Sb and Os and diminished TAC compared to control ( p < 0.001). Furthermore, there was significant inhibition of SOD, CAT and several glutathione-related enzyme activities in sera of PCOS patients with concurrent elevations in superoxide anions, hydrogen and lipid peroxides, and protein carbonyls, along with disrupted glutathione homeostasis compared to those of controls ( p < 0.001 for all parameters). Additionally, a significant negative correlation was found between the elevated levels of heavy metals and TAC, indicative of the role of metal-induced oxidative stress as a prominent phenomenon associated with the pathophysiology of the underlying PCOS. Data obtained in the study suggest toxic metals as risk factors causing PCOS, and thus protective measures should be considered to minimize exposure to prevent such reproductive anomalies.

Due to poor diagnosis breast cancer in women has emerged as the most common cause of death disease in developing countries. Medicinal plants have been used for thousands of years and can be useful in healthcare, especially in developing countries. Ethanol extracts of leaves of fire bush or arta ( Calligonum comosum; EECC), exhibited significant anticancer potencies against two breast cancer cell lines, MCF-7 and MDA 231. These in vitro effects of EECC indicated potential anticancer activities that were determined to be specific since minimal toxicity was recorded against MCF-12, a non-cancerous breast cell line used as a reference. EECC also induced cell cycle arrest in MCF-7 and MDA 231 as revealed by the increased proportions of sub-G1 cells. Fluorescence-activated cell sorter analysis (FACS), utilizing double staining by annexin V-FITC/propidium iodide, revealed that the observed cytotoxic effects were mediated via apoptosis and necrosis. FACS measurement of thegreater in fluorescence intensity, linked with oxidation of DCFH to DCF, revealed that apoptosis was attributable to production of free radicals. EECC-mediated apoptosis was further validated by observation of up-regulation in the "executioner" enzyme, caspase 3. The current findings reveal that EECC exhibits significant, selective cytotoxicity to breast cancer cells, that proceeds via the generation of ROS, which culminates in apoptosis. The anti-proliferative effects of EECC weres further verified by use of a structure-based, virtual screening between its major bioactive polyphenolic constituents and the apoptosis executioner marker enzyme, caspase-3. Based on their glide score values against the active site of caspase 3, some phyto-constituents present in EECC, such as DL-alpha-tocopherol and campesterol, exhibited distinctive, drug-like potential with no predicted toxicity to non-target cells. Taken together, the usefulness of natural phenolic and flavonoid compounds contained in Calligonum comosum were suggested to be potent anticancer agents., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Kumar, Alfhili, Bari, Ennaji, Ahamed, Bourhia, Chebaibi, Benbacer, Ghneim, Abudawood, Alghamdi, Giesy, Al-Sheikh and Aboul-Soud.)

Inflammation is pivotal to the pathogenesis of diabetes mellitus (DM), but pathological alterations of the neutrophil−lymphocyte ratio (NLR), an emerging inflammatory index in DM management, remains understudied. The aim of this study is to examine the relationship between NLR and glycemic control in the Saudi population. Gender, age, WBC count, and fasting blood glucose (FBG) were obtained from Al-Borg Medical Laboratories for 14,205 subjects. Means, prevalence, risk measures, and the diagnostic accuracy of elevated NLR and hyperglycemia (HG) were evaluated. Subjects with elevated NLR (>3) had significantly higher FBG (105.10 ± 0.33 vs. 114.0 ± 2.81) and NLR was significantly elevated in impaired fasting glycemia (IFG; 1.21 ± 0.01 vs. 1.25 ± 0.01) and HG (1.21 ± 0.01 vs. 1.39 ± 0.02). Elevations of NLR in HG but not in IFG persisted across all age groups except young males and elderly females. The prevalence of elevated NLR in hyperglycemic subjects was 4.12% compared to 2.16% in subjects with normal FBG. HG was more prevalent in subjects with elevated NLR (17.33% vs. 12.46%) who had a relative risk (RR) of 1.68 (95% CI = 1.38−2.06, p < 0.0001) and an odds ratio (OR) of 1.94 (95% CI = 1.48−2.56, p < 0.0001) to be hyperglycemic. Nevertheless, NLR failed to discriminate individuals with normal FBG from those with HG based on ROC curve analysis. Pathological fluctuations in NLR may serve as supportive evidence in DM management.

There is a paucity of detailed data related to the effect of senescence on the mitochondrial antioxidant capacity and redox state of senescent human cells. Activities of TCA cycle enzymes, respiratory chain complexes, hydrogen peroxide (H 2 O 2 ), superoxide anions (SA), lipid peroxides (LPO), protein carbonyl content (PCC), thioredoxin reductase 2 (TrxR2), superoxide dismutase 2 (SOD2), glutathione peroxidase 1 (GPx1), glutathione reductase (GR), reduced glutathione (GSH), and oxidized glutathione (GSSG), along with levels of nicotinamide cofactors and ATP content were measured in young and senescent human foreskin fibroblasts. Primary and senescent cultures were biochemically identified by monitoring the augmented cellular activities of key glycolytic enzymes including phosphofructokinase, lactate dehydrogenase, and glycogen phosphorylase, and accumulation of H 2 O 2 , SA, LPO, PCC, and GSSG. Citrate synthase, aconitase, α-ketoglutarate dehydrogenase, succinate dehydrogenase, malate dehydrogenase, isocitrate dehydrogenase, and complex I-III, IIIII, and IV activities were significantly diminished in P25 and P35 cells compared to P5 cells. This was accompanied by significant accumulation of mitochondrial H 2 O 2 , SA, LPO, and PCC, along with increased transcriptional and enzymatic activities of TrxR2, SOD2, GPx1, and GR. Notably, the GSH/GSSG ratio was significantly reduced whereas NAD + /NADH and NADP + /NADPH ratios were significantly elevated. Metabolic exhaustion was also evident in senescent cells underscored by the severely diminished ATP/ADP ratio. Profound oxidative stress may contribute, at least in part, to senescence pointing at a potential protective role of antioxidants in aging-associated disease.

Selenium enhances the cellular antioxidant capacity and alleviates oxidative stress. We investigated the transcriptional and enzymatic activities of selenium-dependent glutathione peroxidase 1 and thioredoxin reductase 1 (TrxR1), and levels of glutathione, hydrogen peroxide, lipid peroxides, and protein carbonyls in primary passage 5 (P5) and senescent passage 25 (P25) and 30 (P30) fibroblasts. Cells were incubated in either standard Dulbecco growth medium (CM1) containing normal plasma selenium levels (0.8 μmol/l), or in CM2, CM3, and CM4 containing 3 μmol/l (5 μmol/l for TrxR1) sodium selenite, L-hydroxyselenomethionine, or Se-methylselenocysteine, respectively. Gene transcripts and activities of both investigated enzymes as well as the levels of reduced glutathione were significantly increased in CM2-, CM3-, and CM4-incubated senescent P25 and P35 cells compared against those incubated in CM1. In congruence, although all oxidative stress parameters including oxidized glutathione were significantly lower in CM2-, CM3-, and CM4-incubated senescent cells compared against those incubated in CM1, such reductions were of significantly higher magnitude in CM3 and CM4 cells compared against those in CM2. In conclusion, organic L-hydroxyselenomethionine and Se-methylselenocysteine are equally more potent at alleviating oxidative stress in senescent cells than inorganic sodium selenite, and thus could be beneficial for use in elderly subjects and those with oxidative stress-associated disease.

Background: Dystrophic Epidermolysis bullosa (DEB) is a rare, severe subtype of epidermolysis bullosa (EB), characterized by blisters and miliary rashes of the skin. Dystrophic EB (DEB) includes variants inherited both in an autosomal-dominant or autosomal-recessive manner. Recessive dystrophic EB (RDEB) is divided into many subtypes and prevails as a result of biallelic genetic mutations in COL7A1 gene encoding type VII collagen, a major stabilizing molecule of the dermo-epidermal junction. The blister formation is mainly due to the variable structural and functional impairment of anchoring fibrils in VII collagen (COLVII), responsible for the adhesion of the epidermis to the dermis. Method: Three Pakistani families (A, B and C) affected with congenital dystrophic epidermolysis bullosa were recruited in the present study. The whole-exome sequencing (WES) approach was utilized for the detection of the pathogenic sequence variants in probands. The segregation of these variants in other participants was confirmed by Sanger sequencing. Results: This study identified a novel missense variant c.7034G>A, p. Gly2345Asp in exon 91, a novel Frameshift mutation c.385del (p. His129MetfsTer18) in a homozygous form in exon no 3, and a previously known nonsense variation (c.1573 C>T; p. Arg525Ter) in exon 12 of COL7A1 gene in families A, B, and C, respectively, as causative mutations responsible for dystrophic epidermolysis bullosa in these families. Conclusion: Our study validates the involvement of the COL7A1 gene in the etiology of dystrophic epidermolysis bullosa. It further expands the COL7A1 gene mutation database and provides an additional scientific basis for diagnosis, genetic counseling, and prognosis purposes for EB patients.

This study investigated the chemical composition, antioxidant and antimicrobial activity of essential oil extracted from Artemisia aragonensis Lam. (EOA). Hydrodistillation was employed to extract EOA. Gas chromatography with flame ionization detection (GC-FID) and gas chromatography-mass spectrometry analyses (GC-MS) were used to determine the phytochemical composition of EOA. Antioxidant potential was examined in vitro by use of three tests: 2.2-diphenyl-1-picrilhidrazil (DPPH), ferric reducing activity power (FRAP) and total antioxidant capacity assay (TAC). Agar diffusion and microdilution bioassays were used to assess antimicrobial activity. GC/MS and GC-FID detected 34 constituents in the studied EOA. The major component was Camphor (24.97%) followed by Borneol (13.20%), 1,8 Cineol (10.88%), and Artemisia alcohol (10.20%). EOA exhibited significant antioxidant activity as measured by DPPH and FRAP assays, with IC 50 and EC 50 values of 0.034 ± 0.004 and 0.118 ± 0.008 mg/mL, respectively. EOA exhibited total antioxidant capacity of 7.299 ± 1.774 mg EAA/g. EOA exhibited potent antibacterial activity as judged by the low minimum inhibitory concentration (MIC) values against selected clinically-important pathogenic bacteria. MIC values of 6.568 ± 1.033, 5.971 ± 1.033, 7.164 ± 0.0 and 5.375 ± 0.0 μg/mL were observed against S. aureus , B. subtills , E. coli 97 and E. coli 57, respectively. EOA displayed significant antifungal activity against four strains of fungi: F. oxysporum , C. albicans , A. flavus and A. niger with values of 21.50 ± 0.43, 5.31 ± 0.10, 21.50 ± 0.46 and 5.30 ± 0.036 μg/mL, respectively. The results of the current study highlight the importance of EOA as an alternative source of natural antioxidant and antibacterial drugs to combat antibiotic-resistant microbes and free radicals implicated in the inflammatory responses accompanying microbial infection.

Polycystic ovary syndrome (PCOS) is a global health concern for women of reproductive age, as 6.5% of women worldwide are affected by this syndrome. PCOS is marked by hyperandrogenism, anovulation, menstrual abnormalities, and polycystic ovaries. Metals such as arsenic, cadmium, lead and mercury are considered to be systemic toxicants/human carcinogens and seem to have devastating effects on humans, even at minimal exposures. One of the probable aetiological factors for PCOS has been identified as oxidative stress. In view of the probable associations among oxidative stress, metal toxicity and PCOS, the present study examined the role of heavy metals in the generation of oxidative stress among females. This prospective study included 106 women (56 women diagnosed with PCOS and 50 women who were not diagnosed with PCOS as control women). There were no significant differences in the sociodemographic characteristics between the two groups except for the irregularity of menses and the presence of acne. The serum As, Cd, Pb, and Hg levels increased and the serum glutathione (GSH) and superoxide dismutase (SOD) levels diminished significantly in the PCOS group compared to the control group at P < 0.001. The SOD levels were negatively correlated with the As and Pb levels at P < 0.05. Additionally, the PCOS group exhibited a strong negative correlation between the GSH and As levels (P < 0.01), GSH and Pb levels (P < 0.05) and GSH and Hg levels (P < 0.01). Furthermore, the As levels were positively correlated with increased levels of Cd, Pb and Hg among PCOS women. Significant positive correlations were observed between Pb and Cd and between Cd and Hg at P < 0.001. The outcome of the study provides clear insight into the role of metal-induced oxidative stress, which plays a vital role in the pathophysiology underlying PCOS and suggests the use of these markers as prognostic tools to reduce the consequences of high-risk exposure to these metals among females., (© 2021. The Author(s).)

Objectives: To assess the oxidation state and gene expression profiles of relevant enzymes in intrauterine growth restriction (IUGR) patients in Saudi Arabia., Methods: Current case-control study involved plasma and placental tissue samples from 25 IUGR patients and 25 healthy pregnant (HP) women attending the Obstetrics and Gynecology Clinic, King Khalid University Hospital, Riyadh, Saudi Arabia, between April and November 2017. We compared hydrogen peroxide, superoxide anions, malondialdehyde, and oxidative stress markers levels and the activities of glutathione-related enzymes (glutathione peroxidase [GPx], glutathione reductase [GR], glutathione S-transferase [GST], glutamate cysteine ligase [GCL], glutathione synthetase [GS], reduced glutathione [GSH], oxidized glutathione [GSSG], and oxidized nicotinamide adenine dinucleotide [NAD + ], and reduced NAD [NADH]) between the 2 groups. We also compared differential expression levels of glutathione-related enzyme genes using reverse transcription-quantitative polymerase chain reaction., Results: Oxidative stress markers significantly differed in IUGR samples, while GSH levels and GPx, GR, GST, GCL, and GS activities and their placental mRNA transcriptional levels were significantly lower. Plasma and placental NAD + levels were also significantly lower, while NADH levels were significantly higher, causing lowered NAD + -NADH ratios in the IUGR group compared to control., Conclusions: Intrauterine growth restriction patients show a metabolic shift in favor of oxidation compared to HP women., (Copyright: © Saudi Medical Journal.)

The prevalence of cancer-associated anemia (CIA) is high, and the mechanisms governing its development remain poorly understood. Eryptosis, the suicidal cell death of red blood cells (RBCs), may account for CIA as it is triggered by clinically approved chemotherapeutics including cisplatin and paclitaxel. Physcion (PSN), an anthraquinone extracted from rhubarb and other plants, has shown great promise as an anticancer agent. However, the potential toxicity of PSN to RBCs remains elusive. RBCs were isolated from heparinized blood, and incubated with 10-100 µM of PSN for 24 h at 37 °C. Hemolysis was photometrically calculated from hemoglobin concentration in the medium at 405 nm, while flow cytometry was employed to investigate cardinal markers of eryptosis. Phosphatidylserine (PS) exposure was detected by Annexin-V-fluorescein isothiocyanate (FITC), intracellular calcium by Fluo4/AM, cellular volume from forward scatter (FSC), and oxidative stress by 2',7'-dichlorodihydrofluorescein diacetate (H 2 DCFDA). PSN induced overt hemolysis at 50 and 100 µM which was not mediated through calcium influx, protein kinase C, casein kinase 1α, or receptor-interacting protein 1. Moreover, PSN caused significant increase in Annexin-V-FITC and Fluo4 fluorescence with no appreciable influence on FSC or DCF values. Accordingly, PSN stimulates premature eryptosis characterized by PS externalization and intracellular calcium overload without cell shrinkage or oxidative damage. In conclusion, this report shows, for the first time, that PSN is cytotoxic to RBCs by inducing hemolysis and programmed cell death which may limit its success as a chemotherapeutic agent.

The present study was undertaken to: i) Determine the levels of oxidative stress (OS) markers, malondialdehyde (MDA), superoxide anions (SOA) and hydrogen peroxide (H 2 O 2 ), in both plasma and placental tissues of recurrent miscarriage (RM) patients in comparison with those of healthy pregnant (HP) and non-pregnant (NP) women; ii) determine the levels of enzymatic antioxidants [glutathione peroxidase (GPx), glutathione reductase (GSR), superoxide dismutase (SOD) and catalase (CAT)], and non-enzymatic antioxidant micronutrients [selenium (Se), zinc (Zn), copper (Cu) and manganese (Mn)] in both plasma and placental tissues of RM patients, in comparison with those of HP and NP women; iii) profile differential expression levels of selected antioxidant and apoptosis-related genes in the placental tissues of RM cases, in relation to those of HP women of matched gestational age, using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The results revealed highly significant increases of all investigated OS markers in plasma and placental tissues of RM patients compared with those of HP women. Moderate, but significant, increases of OS markers were observed in the plasma of HP patients in relation to those of NP women. The activities of antioxidant enzymes exhibited statistically significant decreases in both plasma and placental tissues of RM patients compared with those of HP women. The significantly reduced level of antioxidant enzymes was also evident in the plasma of HP women as compared with those of NP women. Results of RT-qPCR assays clearly indicated that the expression level of apoptosis-related genes [tumor necrosis factor-related apoptosis-inducing ligand ( TRAIL ) and S100A8 ], and pro-inflammatory cytokine genes [tumor necrosis factor-α ( TNF-α ), interleukin ( IL)-6 and IL-8 ] were significantly upregulated in placental tissue of RM cases in relation to those of HP subjects. By contrast, mRNA transcriptional levels of key antioxidant genes ( GPx, SOD, GSR and CAT ) were found to be significantly reduced in placental tissue of RM patients in comparison to those of HP women. In conclusion, our data highlight a plausible cause-effect association between the observed increase in placental OS level and depletion of the activity of antioxidant enzymes. This suggests that OS is a contributing factor in the pathogenesis of idiopathic RM., (Copyright: © Al-Sheikh et al.)

This study was undertaken to examine the activities and levels of major antioxidants/oxidants in cultured human fibroblasts incubated with a sublethal dose of Echis coloratus venom (EcV). Glutathione peroxidase (GPx), catalase (CAT), superoxide dismutase (SOD) and glutathione reductase (GR) activities and gene expression levels as well as reduced glutathione (GSH) levels, and the concurrent hydrogen peroxide (H 2 O 2 ), superoxide anions (SOA), lipid peroxides (LPO) and oxidized glutathione (GSSG) generation rates were assayed in fibroblast cultures and sonicates incubated with 0.5 µg ml -1 medium EcV for 4 h at 37°C. Data indicated that the activities of all antioxidant enzymes were significantly decreased and their corresponding transcripts downregulated in EcV-incubated cells compared to controls (p < 0.001). In contrast, there were parallel equally significant increases in H 2 O 2, SOA and LPO generation rates in venom-incubated cells compared to controls (p < 0.001). Additionally, GSH levels were significantly decreased and those of GSSG were equally significantly increased in venom-incubated cultures compared to controls (p < 0.001) leading to a lowered GSH/GSSG ratio. In conclusion, incubation of fibroblast cultures with EcV resulted in a shift towards oxidative metabolism causing severe OS. This correlated with significant downregulation in the expression levels of all investigated antioxidant genes.

Thioredoxin reductase 2 (TR2) activity, its gene transcripts, and hydrogen peroxide (H₂O₂) generation were examined in biochemically identified early-senescent P20 and senescent P30 fibroblasts subcultured in media (MEM2-MEM8) containing Se concentrations at 1.25, 2.5, 3.5, 5.0, 6.0, 7.0, and 8.0 µM, respectively. Although TR2 activity was moderately increased in P20 and P30 cells subcultured in routine growth medium (MEM1), there were progressive significant activity increases in the same cells subcultured in MEM2-MEM8. Such increases were proportional to Se concentration and peaked in P30 cells incubated with MEM7 and MEM8. H₂O 2 generation underwent progressive increases in MEM1-incubated P20 and P30 cells, peaking in the latter, but was gradually lowered in those incubated with MEM2-MEM8, reaching its lowest values when cells were incubated with MEM7 and MEM8. In parallel, TR2 gene transcripts underwent significant upregulation in P20 cells and higher magnitude upregulation in P30 cells subcultured in MEM2, MEM4, and MEM8 compared to those recorded for P5 pre-senescent cells subcultured in the same media. The computed Km Se values with respect to TR2 activity equaled 3.34 and 4.98 µM for P20 and P30 cells, respectively, with corresponding V max activities of 55.9 and 96.2 nmol/min/mg protein. It is concluded that senescent P30 cells utilize more Se and achieve maximal TR2 activity to combat oxidative injury., Competing Interests: The author declares no conflicts of interest.

Reports related to the effects of Echis coloratus venom (EcV) on the antioxidant capacity of human tissues is very scarce. The present study was undertaken to investigate the activities and gene expression levels of glutathione peroxidase (GPx), glutathione reductase (GR), glutathione S-transferase (GST), superoxide dismutase (SOD) and catalase (CAT), as well as the levels of reduced glutathione (GSH), oxidized glutathione (GSSG) and the generation rates of superoxide anions (SOA), hydrogen peroxide (H 2 O 2 ) and lipid peroxides (LPO) in cultured human fibroblasts incubated with EcV, ascorbate (Asc) and EcV plus Asc at concentrations and incubation periods that maintained cell viability. Results indicated that the activities of all antioxidant enzymes and their corresponding transcripts underwent highly significant decreases and downregulation in EcV-treated cultures (0.5 µg/ml medium for 4 h) compared to venom-free controls (P<0.001). Additionally, there were concurrent equally significant increases in SOA, H 2 O 2 and LPO generation rates in the venom-incubated cultures compared to controls (P<0.001). Results also indicated very significant decreases and parallel equally significant increases in GSH and GSSG levels respectively in the envenomed cultures compared to controls (P<0.001) leading to a drastically lower GSH/GSSG ratio. However, further incubation of the EcV-treated cultures with Asc (400 µM for 12 h) restored the activities and levels of all investigated parameters including the expression levels of the antioxidant genes to control venom-free values. It is concluded that Asc acted to neutralize the increased reactive oxygen species generation, thus ameliorating the EcV-induced oxidative stress and alleviating the downregulation of antioxidant genes.

Objective: Synthetic dyes have been reported to exert detrimental effects on the health of humans. This study evaluated the effects of a diet containing tartrazine (Tz) on rats which included: i) biochemical parameters including hepatic enzymes, kidney functions and profiles of lipids; ii) markers of oxidative stress in cells by measuring concentrations of malondialdehyde (MDA) and glutathione (GSH); iii) activities of selected, key hepatic antioxidant enzymes including catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx); iv) pathologies of liver. Also, protective effects of three doses of curcumin (CUR), a natural food coloring agent, on these parameters in rats that had been co-exposed to Tz., Materials and Methods: Fifty Wistar male albino rats were randomly divided into five groups: Group I, control, where rats were fed a normal diet; Group II, rats were fed normal diets containing 7.5 mg Tz/kg diet, dry mass (dm); In Groups III, IV and V, rats were fed diets containing Tz plus 1.0, 2.0 or 4.0 g CUR/kg diet, dm, respectively. Whole blood was collected after 90 d of exposure, homogenates of liver were prepared and the above analyses were conducted., Results: Exposure to Tz in the diet caused statistically significant (p<0.05) greater concentrations of lipids, hepatic enzymes, and kidney function parameters as well as the indicator of oxidative stress MDA. Alternatively, activities of several antioxidant enzymes (i.e. CAT, SOD and GPx) and concentration of the substrate GSH, an indicator of non-enzymatic antioxidant capability, were significantly (p<0.05) less than those in control rats not exposed to Tz. Tz caused various histopathological changes in livers of rats, which were characterized by hemorrhage and dilatation of the central vein and sinusoids, hepatocyte necrosis, intracellular vacuolization. Co-administration of 2.0 (Group IV) or 4.0 g CUR/kg diet (Group V) with Tz significantly mitigated effects on functions of liver and kidney and the profile of relative concentrations of lipids. CUR significantly (p<0.05), and almost completely, reversed effects on enzymatic and non-enzymatic antioxidant and indicators of oxidative stress about rats fed Tz (Group II) to values in control rats. However, co-administration of 1.0 g CUR with Tz (Group III) exhibited a negligible effect on those parameters. The results of this study suggest benefits of the use of CUR, as a promising natural food additive to counteract oxidative stress caused by dietary exposure to the synthetic dye Tz due to potent protective antioxidant activity., Conclusions: Blending some natural food additives, such as CUR with diets containing synthetic dyes, could moderate potential effects of these artificial dyes. Decreasing or removing toxins in food is an essential step for the amelioration of human health status and decreasing risk of onset or progression of degenerative diseases.

Objective: To investigate the effect of increasing Mn+2 concentrations on superoxide dismutase 2 (SOD2) activity in pre-senescent and senescent cultured fibroblasts, and to determine the Km Mn+2 values required to achieve maximal SOD2 activities in such cells., Materials and Methods: SOD2 activities, and superoxide anion (SOA) generation rates, were assayed in mitochondrial sonicates of young passage 5 fibroblasts sub-cultured in routine growth medium (MEM 1), and in an accurately identified senescent passage 20, 25 and 30 subcultures incubated with media containing supplemental Mn+2 increments equal to 60, 90, 120, 150 and 180 nM (MEM 2, 3, 4, 5 and 6 respectively)., Results: Whereas SOD2 activity did not significantly change in any of the cells sub-cultured in MEM 1, the enzyme underwent progressive significant increases in early senescent passage 20 cells and senescent passage 25 and 30 cells. Such increases were relative to Mn+2 concentration and peaked in value in the senescent cells incubated with MEM 5 and MEM 6. Furthermore, whereas SOA generation rates underwent significant progressive increases in MEM 1-incubated senescent passage 20-30 cells, peaking in value at passage 30, the rates were gradually and significantly lowered in the cells incubated with MEM 2-MEM 6, and reached lowest values in those incubated with MEM 6 (p<0.001 for all comparisons). The computed Km values of Mn+2 with respect to SOD2 in senescent passage 20, 25 and 30 cells equalled 19.2, 39.6 and 54.4 nM respectively with corresponding SOD2 Vmax values of 37.6, 55.9 and 71.4 µmol/min/mg protein., Conclusions: Senescent cells near the end of their replicative life span utilise more Mn+2 and achieve maximal SOD2 activities suggesting that the use of supplementary Mn+2 can help in combating oxidative stress.

The antioxidant activities of superoxide dismutase 1 (SOD1) and SOD2, as well as the levels of the oxidant superoxide anion (SOA) and the micronutrients zinc (Zn), copper (Cu) and manganese (Mn), were assayed in plasma, whole blood and placental tissue of non‑pregnant (NP), healthy pregnant (HP) women and recurrent miscarriage (RM) patients. The results showed that SOD1 and SOD2 activities and the levels of Zn, Cu and Mn in plasma and whole blood of HP women were slightly, but significantly lower, and even more significantly decreased in RM patients compared to those observed in NP women (P<0.05 and P<0.0001, respectively). Additionally, whereas plasma SOD1 and SOD2 activities and Zn, Cu and Mn levels were significantly lower in RM patients, those of whole blood and placental tissue were significantly lower when compared to HP women (P<0.001 and P<0.0001, respectively). Concurrently, there were consistent increases of equal magnitude and statistical significance in SOA levels in all the assayed samples as identified by a comparison between the subjects. The findings thus supported oxidative metabolism and excessive reactive oxygen species generation. The resultant oxidative stress, identified in whole blood and placental tissues of RM patients, may have been a primary cause of RM. Dietary supplementation of Zn, Cu and Mn may be beneficial to these patients pre- and post-conception.

MicroRNAs (miRNAs or miRs) have been advocated as potentially robust and highly stable biomarkers of diverse disease conditions including cancer. The primary aim of this study was two-fold: i) to profile the expression levels of selected mature miRNA signature genes, such as miR-145, miR-195, miR-29 and miR-92, in a paired-study design of 20 colorectal cancer (CRC) tissues from patients versus adjacent neoplasm-free mucosal tissues employing reverse transcription-quantitative polymerase chain reaction; and ii) to examine their expression level in the plasma of the same CRC patients in relation to the age-matched plasma of healthy controls. Statistically significant (P<0.01) increases in miR-29 (2.5) and miR-92 (2.6) were observed in CRC tissues compared with adjacent neoplasm-free mucosal tissues. Profiling of CRC plasma samples showed that the expression levels of circulating miR-29 and miR-92 were significantly higher (P<0.01) than in the age-matched normal plasma. By contrast, miR-145 and miR-195 exhibited significant (P<0.05) decreases in their mean expression levels in CRC tissue samples in relation to the normal tissues. The mean expression levels of miR-145 and miR-195 were significantly lower (P<0.05) in CRC plasma than the healthy controls. Distinct stage-dependent changes in the expression level of the four miRNA gene profiles were observed between stages II and IV plasma of CRC patients relative to the control plasma. Taken together, the results clearly reflect a similar trend for the four miRNA expression levels in tissue and plasma as well as the positive correlation in the levels of miRNAs in tissues and plasma. These findings may be useful to clarify the molecular mechanisms underlying colorectal carcinogenesis and to underscore the potential of the investigated miRNAs as novel early diagnostic biomarkers of CRC.

This study was undertaken to investigate the antioxidant/oxidant status in recurrent miscarriage patients. Antioxidants including glutathione peroxidase (GPx), catalase (CAT), glutathione reductase (GR), reduced glutathione (GSH) and selenium (Se), as well as the oxidants hydrogen peroxide (H2O2), oxidised glutathione (GSSG) and lipid peroxidation were assayed in plasma, whole blood and placental tissue of non-pregnant women (NP), healthy pregnant women (HP), and recurrent miscarriage (RM) patients. Results indicated that all antioxidant activities and levels in plasma and whole blood of HP women were consistently moderately lower, and much more significantly lower in RM patients when both were compared to those seen in NP women (P<0.05 and P<0.001, respectively). Furthermore, whereas plasma antioxidant activities and levels were significantly lower in RM patients, those of whole blood and placental tissue were much more significantly lower when compared with HP women (P<0.001). Concurrent with these findings there were consistent increases of equal statistical significance and magnitude in the levels of all investigated oxidants assayed in all samples when compared in between subjects of the study as indicated above. Data thus illustrated a distinct shift in favor of oxidative reactions and reactive oxygen species (ROS) generation, and very significant decreases in the GSH/GSSG ratios in whole blood and placental tissue of RM patients when compared to HP and NP women (P<0.001). The above noted oxidative stress could have been a major causative factor of recurrent miscarriage.

Fibroblast cultures were used to study the effects of crude Walterinnesia aegyptia venom and its F1-F7 protein fractions on TCA cycle enzyme activities and mitochondrial NAD-redox state. Confluent cells were incubated with 10 μg of venom proteins for 4 hours at 37°C. The activities of all studied TCA enzymes and the non-TCA mitochondrial NADP(+)-dependent isocitrate dehydrogenase underwent significant reductions of similar magnitude (50-60% of control activity) upon incubation of cells with the crude venom and fractions F4, F5, and F7 and 60-70% for fractions F3 and F6. In addition, the crude and fractions F3-F7 venom proteins caused a drop in mitochondrial NAD(+) and NADP(+) levels equivalent to around 25% of control values. Whereas the crude and fractions F4, F5, and F7 venom proteins caused similar magnitude drops in NADH and NADPH (around 55% of control levels), fractions F3 and F6 caused a more drastic drop (60-70% of control levels) of both reduced coenzymes. Results indicate that the effects of venom proteins could be directed at the mitochondrial level and/or the rates of NAD(+) and NADP(+) biosynthesis.

The specific activities of zinc/copper (Zn/Cu)-superoxide dismutase (SOD-1) and manganese (Mn)-superoxide dismutase (SOD-2) were assayed in young passage 5 fibroblasts and in serially subcultured cells that were characterized as senescent at passages 15-35. SOD-1 and SOD-2 activities did not significantly change in senescent and young cells cultured in either routine medium [minimum essential medium 1 (MEM1)], or in Zn, Cu and Mn supplemented medium (MEM2) containing normal human plasma levels of the cations. SOD-1 and SOD-2 activities, however, underwent parallel progressive significant activity increases in senescent passage 20 and 25 cells, which peaked in value in passage 30 and 35 cells subcultured in supplemented medium (MEM3) containing triple human plasma levels of the cations. Concurrently, superoxide radical generation rates underwent progressive significant increases in senescent passage 15-25 cells, which peaked in value in passage 30 and 35 cells subcultured in MEM1 or MEM2. These rates, however, were significantly lowered in senescent cells subcultured in MEM3. We infer that it was only possible to significantly stimulate SOD-1 and SOD-2 activities in senescent MEM3 cultured cells enabling them to combat oxidative stress., (Copyright © 2011 John Wiley & Sons, Ltd.)

Aims: To investigate the effect of senescence and selenium supplementation on glutathione peroxidase (cGPx) and catalase (CAT) activities, and concurrent hydrogen peroxide (H(2)O(2)) generation in subcultured human fibroblasts., Methods: cGPx and CAT activities and H(2)O(2) levels were assayed in presenescent passage 5 and 10 cells, and in senescent passage 20, 25, 30 and 35 cells cultured in routine medium (MEM1) and supplemented media MEM2 and MEM3 containing normal and triple human plasma levels of Se, respectively. Senescent cells were identified by studying their growth and replication states, and by monitoring their activity of key glucose and glycogen degradative enzymes., Results: cGPx activity showed moderate increases in senescent cells at passages 20-35 subcultured in MEM1 or MEM2. This activity underwent highly significant progressive increases in the same senescent cells subcultured in MEM3. In contrast, CAT activity showed progressive, highly significant increases in senescent cells at passages 20-35 regardless of the culture medium type. Concurrent H(2)O(2) generation was significantly increased in passage 15-25 cells and peaked to higher levels in passage 30 and 35 cells cultured in MEM1 or MEM2. These rates, however, were significantly reduced in senescent passage 20-35 cells cultured in MEM3., Conclusions: The highest cGPx activity and coupled lower H(2)O(2) generation were achieved in senescent cells cultured in MEM3., (Copyright © 2011 S. Karger AG, Basel.)

The specific activities of Complexes I-III, II-III, and IV of the respiratory chain, and citrate synthase, were determined in mitochondrial sonicates of six control passage 5 fibroblast cultures, cultivated in growth medium containing fetal calf serum as the only source of ascorbate. The enzymes were also assayed in serially subcultured fibroblasts which were characterized as aged at passage 20 and beyond. Results indicated a significant loss of all enzyme activities in aged cells at passage 20, 25, and 30. Further studies involved maintenance of serially subcultured cells in serum free media to which increasing ascorbate concentrations (100, 200, and 300 micromol 1(-1)) were added. Results indicated that ascorbate at 100 micromol 1(-1) was not sufficient to restore any of the enzyme activities in aged cells. An ascorbate concentration of 200 micromol 1(-1) however, could totally restore Complex IV and citrate synthase activities, but had no effect on complexes I-III and II-III activities which required 300 micromol 1(-1) ascorbate to be partially or totally restored respectively. In conclusion, this study demonstrates an age related drop in mitochondrial respiratory chain activity in cultured human fibroblasts. Enzyme activities could be completely or partially restored in the presence of double or triple normal human plasma ascorbate concentrations., (2010 John Wiley & Sons, Ltd.)

The level of adenosine deaminase (ADA; EC 3.5.4.4) was estimated at different passages in six confluent fibroblast cultures established from forearm skin biopsies of healthy adult normal volunteers. After determination of the zinc concentration in standard growth medium, ADA activity was estimated at different passages of subculture in media with different zinc concentrations. The results indicated that the specific activity of ADA in control confluent skin fibroblast cultures (passage 2) cultivated in standard growth medium containing 15.4 microM zinc (similar to that present in normal human plasma) was equal to 226.6+/-19.64 micromol min(-1) mg(-1) protein. The results showed that there were no significant changes in ADA specific activity in any of the control cultures as the zinc concentration of the medium was increased. To characterize the passage of subculture at which fibroblasts enter the ageing phase, three marker enzymes were assayed namely, phosphofructokinase, lactate dehydrogenase and glycogen phosphorylase. The result showed that the cells enter the ageing phase at passage 20 and beyond. Further investigation showed that ADA activity of serially subcultured confluent cultures cultivated in standard growth medium significantly dropped at passages 20, 25 and 30. ADA activity however was not significantly altered in cells at passage 2, 10 and 15 cultivated in standard growth medium and in the presence of higher zinc levels (23.1, 34.6, 53.8 and 73.1 microM). Furthermore there was significant lowering of ADA activities in cells at passages 20, 25 and 30 when cells were cultured in the presence of 15.4, 23.1 and 34.6 microM zinc. Such lowered activities of ADA were restored to normal when the cells were cultured in the presence of higher zinc concentration equal to 53.8 and 73.1 microM. From the results we concluded that it is possible to restore ADA activity in aged skin fibroblasts to normal levels by raising the zinc concentration in the culture medium to four or five times the control normal plasma zinc level., (Copyright 2003 John Wiley & Sons, Ltd.)

Crude venom of Echis coloratus was separated into seven protein fractions using 7% preparative native polyacrylamide gel electrophoresis. The effect of crude venom and seven venom protein fractions (F1-F7) from Echis coloratus on key metabolic activities of fibroblast cultures was investigated. Confluent cultures were incubated with the venom proteins for 3 h at 37 degrees C. The specific activity of phosphofructokinase, was significantly lowered upon incubation with the crude venom and with fractions 2, 3, 4 and 6. Citrate synthase activity was significantly lowered by the crude venom and by fractions 2 and 3. Glycogen phosphorylase activity was significantly increased by the crude venom and by fractions 2, 3, 4 and 6 leading to a significant concurrent drop in glycogen content. Creatine kinase activity was significantly increased by the crude venom and by fractions 3, 4, 5 and 6. Cellular ATP levels rose significantly upon incubation with the crude venom and with fractions 3, 4, 5 and 6. Incubation of cell sonicates with all the venom proteins did not significantly alter the activity or content of any of the studied parameters., (Copyright 2002 John Wiley & Sons, Ltd.)

The level of adenosine deaminase (EC. 3.5.4.4), was estimated in plasma of 389 healthy males and 493 healthy females in order to establish a normal reference range for Saudis. Using the continuous spectrophotometric method, the reference ranges were calculated in two ways using the mean +/- 2 SD and the 2.5th - 97.5th percentile value methods. In both methods of calculation, a slightly higher range was observed for children as compared to adults. The method of 2.5th - 97.5th percentile values brought almost all of our subjects within the recommended range of 11.5 - 25 U/l. In the current study, the normal range for adenosine deaminase totalled 15.0 - 23.2, 14.8 - 23.6, 15.0 - 23.0 and 16.7 - 24.6 U/l for the overall population, all males, females, and children, respectively. The ranges are discussed in the light of significantly different results obtained by the two calculation methods and recommendation of an appropriate method for healthy Saudis, namely the 2.5th - 97.5th percentile values. The choice of the Ellis and Goldberg kinetic continous monitoring method for the estimation of plasma ADA levels in the current investigation is also hereby justified.

Cultured human fibroblasts were used to study the effect of a crude extract of Cerastes cerastes gasperetti venom on the activity of a profile of key enzymes of metabolism. A single concentration of the crude venom was incubated with confluent fibroblasts established from six normal subjects for a period of three hours. A dramatic reduction in the specific activities of glucose and glycogen degradative enzymes was observed (23.7 +/- 3.9%, 36.3 +/- 8.7% and 71.1 +/- 5.7% of control for citrate synthase, glucose-6-phosphate and phosphofructokinase respectively). Furthermore, the specific activity of creatine kinase was doubled. No significant change in activity of three transaminases was noticed. Incubation of the same concentration of venom for the same period of time with serum did not result in any change in the activity of the enzymes studied. It is suggested that the cells mobilize stored phosphocreatine for the production of adenosine triphosphate (ATP) to compensate for the reduced rate of sugar catabolism. Furthermore, it is hereby suggested that the effects noticed on the enzyme activities are not directed at the enzyme protein itself, but are of mediated nature.

There appear to be at least two underlying aetiologies for combined carboxylase deficiency; firstly, a failure of biotinylation of apocarboxylases due to a mutation of holocarboxylase synthetase (EC 6.3.4.10) which results in an enzyme with a high Km with respect to biotin and secondly, a failure of biotinylation due to a lowered availability of biotin due to biotinidase deficiency (EC 3.5.1.12). In both these disorders secondary defects of all four biotin-dependent carboxylases result which in turn causes the excretion of the metabolites characteristic of the isolated carboxylase deficiencies. In addition, both disorders respond biochemically and clinically to the administration of large amounts of biotin.

Two Vietnamese siblings with an isolated deficiency of 3-methylcrotonyl coenzyme A carboxylase in leucocytes and cultured fibroblasts are described. Both children excreted massive amounts of 3-methylcrotonylglycine and 3-hydroxyisovaleric acid. There was no in vivo or in vitro biochemical response to biotin. Apart from an attack of vomiting leading to subcoma in the elder sib four weeks after arrival in the Netherlands, the children were in good health. There were no signs of delayed mental development.

The causes of congenital lactic acidaemia are outlined. Isolated pyruvate carboxylase deficiency is reviewed in detail with a report of a recent case and a discussion of the biochemical consequences. Other causes of defective pyruvate carboxylation are described, particularly the combined carboxylase defects.