Paradigm shift in eukaryotic biocrystallization

Despite the widespread occurrence of crystalline inclusions in unicellular eukaryotes, scant attention has been paid to their composition, functions, and evolutionary origins, assuming just their inorganic contents. The advent of Raman microscopy, still scarcely used for biological samples, allowed chemical characterization of cellular inclusions in vivo. Using this method, herein we provide a substantial revision of the cellular crystalline inclusions across the broad diversity of eukaryotes examining all major supergroups. Surprisingly, here we show that 80 % of these crystalline inclusions contain purines, mostly anhydrous guanine (62 %), guanine monohydrate (2 %), uric acid (12 %) and xanthine (4 %). Hence, our findings indicate that purine biocrystallization is a very general and an ancestral eukaryotic process operating by an as-yet-unknown mechanism. Purine crystalline inclusions are high-capacity and rapid-turnover reserves of nitrogen of a great metabolic importance, as well as optically active elements, e.g., present in the light sensing eyespots of flagellates, possessing even more hypothetical functions. Thus, we anticipate our work to be a starting point for more in-depth studies of this phenomenon on the detailed level spanning from cell biology to global ecology, with further potential applications in biotechnologies, bio-optics or in human medicine.

Inhibition of Ceramide Synthesis Reduces α-Synuclein Proteinopathy in a Cellular Model of Parkinson’s Disease

Parkinson’s disease (PD) is a proteinopathy associated with the aggregation of α-synuclein and the formation of lipid–protein cellular inclusions, named Lewy bodies (LBs). LB formation results in impaired neurotransmitter release and uptake, which involve membrane traffic and require lipid synthesis and metabolism. Lipids, particularly ceramides, are accumulated in postmortem PD brains and altered in the plasma of PD patients. Autophagy is impaired in PD, reducing the ability of neurons to clear protein aggregates, thus worsening stress conditions and inducing neuronal death. The inhibition of ceramide synthesis by myriocin (Myr) in SH-SY5Y neuronal cells treated with preformed α-synuclein fibrils reduced intracellular aggregates, favoring their sequestration into lysosomes. This was associated with TFEB activation, increased expression of TFEB and LAMP2, and the cytosolic accumulation of LC3II, indicating that Myr promotes autophagy. Myr significantly reduces the fibril-related production of inflammatory mediators and lipid peroxidation and activates NRF2, which is downregulated in PD. Finally, Myr enhances the expression of genes that control neurotransmitter transport (SNARE complex, VMAT2, and DAT), whose progressive deficiency occurs in PD neurodegeneration. The present study suggests that counteracting the accumulation of inflammatory lipids could represent a possible therapeutic strategy for PD.

Complex Inclusion Bodies and Defective Proteome Hubs in Neurodegenerative Disease: New Clues, New Challenges

A healthy physiological environment of cells represents the dynamic homeostasis of crowded molecules. A subset of cellular proteome forms protein quality control (PQC) machinery to maintain an uninterrupted synthesis of new polypeptides and targeted elimination of old or defective proteins. The process of PQC may get overwhelmed under specific genetic mutations, environmental stress conditions, and aging-associated perturbances. Many of these conditions may lead to the generation of various types of aberrant protein species that may or may not accumulate as large cellular inclusions. These proteinaceous formations, referred to as inclusion bodies (IBs), could be membrane-bound or membrane-less, cytoplasmic, or nuclear. Most importantly, they could either be toxic or protective. Under acute stress conditions, the formation of aggregates may cause proteostasis failure, leading to large-scale changes in the cellular proteome compositions. However, the large insoluble IBs may act as reservoirs for many soluble proteins with high aggregation propensities, which can overwhelm the cellular chaperoning capacity and protein degradation machinery. The kinetic equilibrium between folding and unfolding, misfolding, and refolding; aggregation and degradation is perturbed in one or many neurodegenerative disorders (NDDs) associated with dementia, cognitive impairments, movement, and behavioural losses. However, a detailed interplay of IBs into the manifestation of the NDDs is unknown, and a very primitive knowledge of structural compositions of amyloid inclusions is present. The present article presents a brief evolutionary background of IBs; their functional relevance for prokaryotes, plants, and animals; and associated involvement in neuronal proteostasis.

Enhanced accumulation of reduced glutathione by Scopoletin improves survivability of dopaminergic neurons in Parkinson’s model

Parkinson’s disease (PD) is a neuromotor disorder, primarily manifested by motor anomalies due to progressive loss of dopaminergic neurons. Although alterations in genetic factors have been linked with its etiology, exponential accumulation of environmental entities such as reactive oxygen species (ROS) initiate a cyclic chain reaction resulting in accumulation of cellular inclusions, dysfunctional mitochondria, and overwhelming of antioxidant machinery, thus accelerating disease pathogenesis. Involvement of oxidative stress in PD is further substantiated through ROS induced Parkinsonian models and elevated oxidative markers in clinical PD samples; thereby, making modulation of neuronal oxidative load as one of the major approaches in management of PD. Here we have found a potent antioxidant moiety Scopoletin (Sp), a common derivative in most of the nootropic herbs, with robust neuroprotective ability. Sp increased cellular resistance to ROS through efficient recycling of GSH to prevent oxidative damage. The Sp treated cells showed higher loads of reduced glutathione making them resistant to perturbation of antioxidant machinery or neurotoxin MPP+. Sp could restore the redox balance, mitochondrial function, and prevented oxidative damage, leading to recovery of dopaminergic neural networks and motion abilities in Drosophila genetic model of PD. Our data also suggest that Sp, in combination increases the therapeutic potency of L-DOPA by mitigating its chronic toxicity. Together, we highlight the possible ability of Sp in preventing oxidative stress mediated loss of dopaminergic neurons and at the same time enhance the efficacy of dopamine recharging regimens.

Iron Redox Chemistry and Implications in the Parkinson’s Disease Brain

The etiology of Parkinson’s disease (PD) is linked with cellular inclusions in the substantia nigra pars compacta region of the brain that are enriched in the misfolded presynaptic protein α-synuclein (αS) and death of the dopaminergic neurons. Brain iron homeostasis governs both neurotransmission and neurodegeneration; hence, the role of iron in PD progression and neuronal health is apparent. Elevated iron deposits become prevalent in the cerebral region upon aging and even more so in the PD brain. Structural as well as oxidative modifications can result from coordination of αS with redox active iron, which could have functional and/or pathological implications. In this review, we will discuss iron-mediated αS aggregation, alterations in iron metabolism, and the role of the iron-dopamine couple. Moreover, iron interactions with N-terminally acetylated αS, the physiologically relevant form of the human protein, will be addressed to shed light on the current understanding of protein dynamics and the physiological environment in the disease state. Oxidative pathways and biochemical alterations resulting from aberrant iron-induced chemistry are the principal focus of this review in order to highlight the plethora of research that has uncovered this emerging dichotomy of iron playing both functional and disruptive roles in PD pathology.

Quali alterazioni dell’esame urine possono preludere ad un interessamento renale della malattia di Fabry

The markers of renal involvement in Anderson-Fabry disease are defects of urine concentration, presence of cells with lipid cytoplasmatic inclusions (mulberry bodies) and podocyturia. The loss of urine concentrating capacity is not easy to detect and the search for cellular inclusions is a complex technique. Moreover, none of the markers has any clear correlation with the stage of the disease. The occurrence of podocytes in the urine (podocyturia) correlates with both renal involvement and clinical outcome; therefore, podocyturia seems to be a promising early indicator of nephropathy. However, a common agreement on the laboratory assay used to measure is still needed.

Rare Tauopathies

Tauopathies are rare neurodegenerative disorders related to microtubule-associated protein tau, which functions to stabilize microtubules. Pathological changes caused by overexpression or hyperphosphorylation of tau lead to the disengagement of tau from microtubules and accumulation of toxic intracellular inclusions. Tau pathology is the underlying mechanism for several sporadic and genetic disorders. These are collectively known as tauopathies. Each tauopathy is differentiated from others by its neuropathological features such as the presence of specific isoforms of tau, type of cellular inclusions, and the regions of the brain affected. Neuropathological features, with a few exceptions however, do not correspond to distinct clinical phenotypes. There is considerable phenotypic overlap between the different tauopathies. Interaction between tau and other protein inclusions further alters the clinical phenotype.Recent advances in the development of tau biomarkers, especially the development of tau radioligands used in positron emission tomography neuroimaging, and a better understanding of biology and pathology of tau are important first steps toward the ultimate goal of accurate diagnosis and disease modification in tauopathies.

PHARMACOGNOSTIC INVESTIGATION OF GALANTHUS WORONOWII LOSINSK. AND GALANTHUS NIVALIS L. HERBAL PHARMACEUTICAL SUBSTANCES (MICROSCOPIC AND MACROSCOPIC ANALYSIS)

Objective: Today drug produced from snowdrop species (Galanthus woronowii Losinsk. and Galanthus nivalis L.) used in Russian traditional medicine for nervous and cardiovascular systems disorders treatment.Pharmacognostic study of fresh snowdrop plants including macroscopic and microscopic (morpho-anatomical diagnostic features) evaluation for identification of herbal pharmaceutical substances (HPS).Methods: Macro- and micro-scopic evaluation was carried out according to general pharmacopeial monographs of State Pharmacopoeia of Russian Federation XIII ed., Photographs were obtained by the microscope “Altami 139T” (10× eyepiece and lenses: 4×, 10×, 40×, 100×) with a digital camera eyepiece UCMOS05100KPA; images were processed using Altami Studio program.Results: In a pharmacognostic study of G. nivalis and G. woronowii HPS linear dimensions were determined. Several microscopic diagnostics and anatomical signs of snowdrops were investigated: Adaxial and abaxial leaf epidermis; epidermis of corolla, peduncle; internal and external outer scale epidermis, internal and external storage scale epidermis, and sizes of cells and cellular inclusions (starch grains and calcium oxalate raphides). G. woronowii and G. nivalis HPS possess differences both in the micro and macro levels in the linear dimensions. In general, dimensions of G. nivalis organs are much smaller than G. woronowii ones, this aspect is also expressed in the cell structures linear dimensions. The complex of macro- and micro- diagnostic signs allows to identify the snowdrop species.Conclusion: The results of the investigation can be used in routine quality control and for inclusion of pharmacopeial monographs for snowdrop HPSs.

Bioplastic Polyhydroxyalkanoate (PHA): Recent Advances in Modification and Medical Applications

A wide variety of bacteria are found to be the tiny factories in the production of polyhydroxyalkanoate (PHA) biopolymer. PHA is the polyesters of 3-hydroxyalkanoic acids which occur in bacteria when the bacteria is subjected to nutrient limitation and simultaneously fed with an excess amount of carbon. This unfavorable condition forces the bacteria to store carbon in the form of resorbable cellular inclusions called PHA. Biosynthesized PHA has the ability to replace the currently feasible harmful petroleum based plastics to biobased plastics. PHA research is being focused mainly on two facts - bulk production of environment friendly low-cost PHA and functional group modification for multiple applications to mankind. Many companies are already producing PHA with highly tunable properties and are looking into economically feasible technologies for mass production of PHA. The core focus of PHA research includes a selection of potential PHA producers and low to zero cost carbon sources such as carbon containing wastages of household, farms and industries. This challenge of “trash to treasure” still remains to attain. Tunable properties of PHA have made them a more interesting biomaterial to blend with suitable biopolymers including bioactive compounds. Under precise physiological environment, PHA blends can deliver promising mechanical properties, acting as effective drug carriers and showing time bound degradation. Perhaps desirably tuned PHA may address many health issues including orthopedics - load bearing cartilage, artificial membranes for kidneys, heart and wound management. PHA has high immunotolerance, low toxicity and sustained biodegradability, which have attracted diverse scientist with many medical advancements such as bioabsorbable sutures and 3D structures. In the near future, it is expected to derive many smart auto controllable products from PHA such as microsphere, which could be utilised for a range of applications much more than just drug delivery. Furthermore, naturally produced hybrid PHA will be an interesting candidate as they possess essential properties for targeted applications without further artificial blending or incorporating any components.