PACAP Protects Against Ethanol and Nicotine Toxicity in SH-SY5Y Cells: Implications for Drinking-Smoking Co-morbidity

Abstract

The detrimental effects of heavy drinking and smoking are multiplied when the two are combined. Treatment modalities for each and especially for the combination are very limited. Although in low concentration, alcohol and nicotine, each may have beneficial effects including neuroprotection, their combination, instead of providing additive protection, may actually lead to toxicity in cell cultures. Pituitary adenylate cyclase-activating polypeptide (PACAP) is an endogenous 38 amino-acid peptide with demonstrated protection against neuronal injury, trauma as well as various endogenous and exogenous toxic agents. The aim of this study was to investigate whether PACAP may also protect against toxicity induced by high alcohol, high nicotine, or the combination of low alcohol and nicotine concentrations, and if so, whether this effect was mediated via PAC1 receptor. We used the neuroblastoma-derived SH-SY5Y cells and applied various colorimetric assays for determination of cell viability or toxicity. Results indicate that PACAP blocks toxicity induced by high alcohol and high nicotine as well as their combination at low concentrations. The effects of PACAP in turn were blocked by the PACAP antagonist (PACAP 6-38), indicating involvement of the PACAP receptor PAC1 and possibly vasoactive intestinal peptide (VIP) receptors in PACAP's protection. Moreover, no combined toxicity of low alcohol and low nicotine could be detected in calcium-free medium. These findings suggest possible beneficial effects of PACAP in preventing alcohol and nicotine toxicity and that calcium contributes to the damage induced by combination of low alcohol and nicotine in SH-SY5Y cells.

Nicotine protects against manganese and iron-induced toxicity in SH-SY5Y cells: Implication for Parkinson's disease

“…Each cell viability study was run in sextuplicate (i.e., 6 replicates) and a minimum of 4 assays were conducted for each experimental manipulation. Determination of cell viability was done by 3, (4,5-dimethylthiazol-2yl)-2,5diphenyltetrazolium bromide (MTT) colorimetric assay according to the manufacturer's protocol as described previously (Manavalan et al, 2017;Getachew et al, 2018). Briefly, the yellow MTT tetrazolium salt (0.5 mg/ml) was dissolved in phosphatebuffered saline (PBS) with 10 mM (4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES).…”

“…Cellular models of substantia nigra dopamine containing neurons include neuroblastomaderived SH-SY5Y cells. We and others have used this cell line extensively to investigate mechanism of neurotoxicity as well as potential novel neuroprotective agents (Manavalan et al, 2017, Han et al, 2018Getachew et al, 2018;Omura et al, 2018;Saksonová et al, 2018). In this regard, protective effects of nicotine or curcumin against toxicity induced by selective dopaminergic toxins, including salsolinol and rotenone have been observed (Copeland et al, 2005;Qualls et al, 2014).…”

Review on PACAP-Induced Transcriptomic and Proteomic Changes in Neuronal Development and Repair

“…A more severe injury has been described in PACAP knockout mice in models of cerebral ischemia [ 20 ], in spinal cord traumatic injury [ 21 ] and in retinal ischemia [ 22 ]. Not surprisingly, exogenous PACAP is a very potent neuroprotective agent, as proven by dozens of neuronal injury models, both in vitro and in vivo [ 16 , 17 , 18 , 23 , 24 , 25 ].…”

“…In vitro, PACAP upregulates several important genes and proteins involved in cellular protection against various harmful stimuli. For example, PACAP has been shown to be protective against toxicity induced by several substances, such as ethanol, nicotine [ 23 ], ceramide [ 69 , 100 ], 6-hydroxydopamine [ 101 ], the HIV envelope protein [ 102 ] and cisplatin [ 103 ]. The strong neuroprotective property of PACAP can also be observed in vivo in several different models of neuronal injury.…”

Pituitary Adenylate Cyclase-Activating Polypeptide: A Promising Neuroprotective Peptide in Stroke

“…Regarding neuroprotection, PACAP is engaged in endogenous protective mechanisms in the acute and chronic cell stress-response [10]. PACAP is generally upregulated in the CNS, and acts against neural damage from several harmful agents, such as kainic acid [74], ethanol, nicotine [75], oxidative stress-related agents [76], glucotoxicity, hypoglycemia-induced toxicity [77], betaamyloid peptide [78], and thrombin [79]. Administration of exogenous PACAP improved the outcomes in a variety of animal models, including traumatic brain injury [80], stroke [81], retinal ischemia [82], spinal cord injury [83], Parkinson's disease [84], Huntington's disease [85], and spinobulbar muscular atrophy [86].…”